What are reasonable temps?
http://enthusiast.hardocp.com/...wxMCwsaGVudGh1c2lhc3Q=
The lowest load temp at stock fan speeds there is 89C so the 8800GT didn't have reasonable temps either.
Originally posted by: chizow
As for the 8800GT, again, a poor example, as that card didn't have thermal issues beyond the stock fan spinning at only 29%. The difference is it still ran within reasonable temps at both idle and load, even while overclocked, which is a stark contrast compared to similar fan speed problems with the 4850 and 4870 where idle/load temps were hitting 80-90/100C respectively.
Originally posted by: chizow
Because given similar process, die size is going to scale with total transistor count and larger dies typically take more power to operate than smaller ones.
Pure misinformation? Really? How much power does your 4850 take to run at 625MHz? How much does a 4870 take to run at 750MHz? How much is this article claiming in order to run at 850MHz? Do you think the single slot cooler is sufficient in cooling the 4870 at 750MHz? What kind of overclocks are end-users seeing with the 4870 and what kind of factory OC variants are available for purchase?
As you can see, people aren't undervolting their 4870s to achieve higher clock speeds.... there's no need for top sekret test data for RV770 to verify how live samples out in the wild are behaving. I guess you can believe ATI has some magical solution to extract more performance out of an RV770 die on the same process and have really just been holding back for the last 7 months since launch.
Again, I don't need to know the max thresholds from any white paper, I just have to look at what's available on the market mixed with end-user reports that show very little success overclocking to the expected 4890 speeds of 850MHz. Simply put, if ATI was able to get more performance out of their RV770, why haven't they, why would they leave performance on the table when they've trailed GT200 since launch and Nvidia in the market in general since G80?
As for the 8800GT, again, a poor example, as that card didn't have thermal issues beyond the stock fan spinning at only 29%. The difference is it still ran within reasonable temps at both idle and load, even while overclocked, which is a stark contrast compared to similar fan speed problems with the 4850 and 4870 where idle/load temps were hitting 80-90/100C respectively. 8800GT OC Thread at launch. You'll see plenty of users, including myself, had no issues overclocking the 880GT with the stock cooler, especially once fan speed was increased to 40-50%.
Furthermore, the 8800GT and G92 are a poor choice as comparison because this architecture went on to produce the 650MHz GTS, 675MHz GTX and many 700MHz+ OC variants, so clearly Nvidia wasn't hitting any thermal or design walls with the 600MHz GT.......
Rofl, but dreaming up a 850MHz with 1000SP and 48TMU based on the same core and same process isn't pure fantasy, especially given the lack of retail or user feedback as proof of concept for even the clockspeed bump? Again, just look at ATI's design and product decisions and overall market position over the past few years. Its obvious they scale their parts based on clockspeed and leave very little room for clock increases on the high-end. If validating and achieving such clocks were so simple, it begs the question as to why ATI isn't selling a faster part given they've trailed Nvidia in performance since G80. Clearly they would've benefitted from a faster part, yet they were unable to produce one. Honestly its just common sense at this point, no need for "intimate knowledge" of their technical data.
So tell us all, how does a 4870 perform when overclocked 10-13%? You can hit 830MHz at stock volts, lets see what you get with water cooling and a voltage increase, should hit 850MHz easy right? I mean that's what the RV790 is supposed to be, you should be able to get that extra 20MHz np given how well ATI parts have overclocked all these years.Originally posted by: thilan29
I myself can get to 830MHz (others have stated similar findings) at stock volts (this was tested before I switched to watercooling) so imagining that with a few tweaks and better yields they could get to 850 is not a stretch but I really can't guess whether they would actually go to that speed.
Sure I can, in this case all factors should favor the ATI chip, as it has the benefit of fewer transistors, smaller process and smaller die size, yet it still draws more power and runs hotter than the GTX 260. Its not like they're using a different fab either, so no advantage or disadvantage there.See Cookie Monster's post above...the 2 are completely different architectures so you can't do direct comparisons as you are doing.
So again, do you think the same conclusion would be accurate when comparing the 4850 and 4870? The difference between the cores is clockspeed, yet based on that AT analysis, it would lead you to the same conclusion that the RV770 is less efficient per mm^2 than the RV770....Again, its obvious RV770 is less power efficient compared to GT200 and any efficiency comparison based on die size also goes away once you account for clockspeed differences (again compare GTX 280 to 4850 or GTX 285 FTW to 4870).There's a flaw in that test as there's a flaw in you making generalizations of 2 different architectures of which you have no intimate knowledge.
Idle temps in the 50s-60s with load temps, even overclocked in the 70s-80s. Those results are consistent throughout the thread I linked. The HardOCP link uses their own infrared thermometer which by itself doesn't tell us much if we don't know relative temps for the software diode readings. Still, its obvious even their 8800GT results are much better than the 80-90C idle and 90-100C load temps of the 4850s and 4870s at launch, which couldn't even be adjusted until a few driver updates later.Originally posted by: thilan29
What are reasonable temps?
http://enthusiast.hardocp.com/...wxMCwsaGVudGh1c2lhc3Q=
The lowest load temp at stock fan speeds there is 89C so the 8800GT didn't have reasonable temps either.
Yep, it absolutely should, and if it doesn't its most likely a flaw in process or execution. In other cases, decreases in heat/power consumption are negated by core clock increases, which necessitate higher power draw and greater heat output (see G92 to G92b). With GT200b B2 there wasn't any significant benefit so it went back for a respin, resulting in B3 which clearly resulted in lower power draw and heat output. Similar was seen with R600 to RV670 on the ATI side.Originally posted by: Cookie Monster
That doesn't answer my question. Let me ask you, is the power consumption going to be different if chip A has a larger die than chip B, knowing that chip A and B are identically the same in terms of spec?
Certainly better than treating RV790 as the "White Rhino" chasing some "Pie in the Sky". Again, its not just based on user reports, its based on real product that is not significantly different than what RV790 is rumored to be along with the very real lack of overclocked RV770 products that would give significant assurance such a product might be feasible.Hmm, Im not sure what you mean here. Unless you mean that your basing your claims on user reports from the internet and then claiming these as absolute "fact" and evidence.
They wouldn't, its a rhetorical response to your claim a clock speed increase to 850MHz wouldn't necessitate an increase in power draw. Of course this directly flies in the face of one of your own corrections with regard to the GTX 285, where you made sure to point out an increase in clockspeed would certainly be accompanied by an increase in power draw.Why would one undervolt to achieve higher clocks in the first place???
As already covered above, its more than just the results of internet users, its based on available product, or more accurately, lack thereof. Also, weren't you just claiming the theoretical limits of 55nm was 1.26V? Where'd you pull that bit of info and if there is any credibility to it, why would you think RV770 has any additional headroom given its already pulling 1.26V to run at 750MHz? As for having little success overclocking, well I guess I'm just used to more than 10% increases to clockspeed, not to mention even those in this thread seem unable to hit 850MHz, the reported speed of RV790.Yet you come out here and claim it as some "fact" when its clear that your just guessing basing your evidence from the internet users. Some of these same end users your basing your claim on have been denying your claims about "very little success overclocking" but you refuse to listen.
Yep I have read the article and if you had as well you'd recall direct mentions of their product timelines with the following general theme:The target MSRP of the HD4870 was $299. The GTX280 was going for $649. If you haven't read the article from AT about the background of RV770, even the engineers who worked on this project were surprised to see that the fastest RV770 at the time was about 80~95% (depending on app) performance of the GTX280. If you haven't figured it out, ATi has changed their market strategies ever since RV670. They have abandoned the "monolithic GPU design" to performance single GPU design then filling the gap with multi core variants ala X2 configurations of their performance chips for the high end.
The difference is we know the 4870 and 4850 run hot based on power draw, which is very different from your poor choice of singling out the 8800GT, which doesn't draw as much power and scales extremely well with clockspeeds.Hmm, yet you were claiming that the HD4870/HD4850s were hot at their "max thresholds", when it fact the fan on the stock cooling of a HD4870 is running at 20% which is infact the lowest value you can go down using the ATis CCC. Up the fan a notch, and your going to see the same result as you did with the 8800GTs.
Again, where's the professor when you need him. Whatever the card's actual TDP is what it comes down to with thermal characteristics. Again, that heat is either on the GPU, in your case, or in your room, but that doesn't change the fact a 4850/4870 is generating more heat relative to its comparably performing parts. Again, given the chip is smaller, has fewer transiors and is on a smaller process (than 65nm GT200), that points to inefficiency in design and/or leakage which necessitates more power in order to stably run at higher frequencies. As you increase frequency you'll eventually reach a point where additional power and cooling are no longer effective in maintaining stability. Feel free to have the engineers over in the CPU forum explain this to you more clearly.What im trying to say here is that when it comes to thermal characteristics, it comes mostly down to cooling not the actual chip itself. Any modern GPU chip will hit high 90C and over unless its the low low end), whether its an ATi chip or nVIDIA. The single slot design held the G92 back, and its was a hot card (not to mention the cards stock cooling went through a revision because of this). The 8800GTS on the other hand was a cooler card with higher clocks. Why? a beefy dual slot cooler. Likewise the stock cooler on the HD4870 could possibly be holding the card back. Yet they dont require more cooling than the stock, because there is no need for such SKU. An HD4850X2 fills that gap nicely, and gives its competition a rough time. Unlike nVIDIAs lineup, the consistency in different SKUs allows them to differentiate one another where as with nVIDIA you could possibly spend less
How is it going OT? I'm trying to figure out the source of all this unbounded optimism with regard to RV790, I just simply can't find any. Once again, you've made various claims regarding ATI/Nvidia that you simply can't back up and are historically untrue.Its going well OT now so Im going to stop because I cant seem to have a decent discussion with you chizow (no offence though). Its hard to do so when one thinks company As product is just about superior than company Bs released/unreleased products in every possible imaginative way while justifying your absurd facts(?) on this "common sense" and supposed internet user claims.
Actually its pretty obvious why Nvidia is leaving performance on the table, they're still winning. I'm also sure its a major incentive and revenue stream for their board partners, as Nvidia charges them the same bill of materials for all reference parts. Partners are allowed to bin and market them as they see fit, however, they're also responsible for providing warranty on those parts.Originally posted by: SlowSpyder
All companies 'leave performance on the table' for yields. My 4870 happily churns along at 825MHz as it is. Others are getting 830+... even on reference coolers. AMD would have to lower bin a lot of RV770's and see them as 4850's or whatever if they don't make 830MHz. On the other hand they compete very nicely with Nvidia at 750MHz, and will get more chips that can obtain that speed. Why do we see so many GTX260/280's approaching 700MHz? Why didn't Nvidia go for that speed? Same reason AMD was happy with 750MHz. It met their performance goals and they were happy with the yields they'd get at that speed.
Yeah we've already been over this though, you have 1 part, compared to ATI = every part.I can pick a bad NV overclocker too. http://www.hardocp.com/article...IxLDYsLGhlbnRodXNpYXN0 This GPU overclocked from 500 to 530MHz on Nvidia's flagship product. See? Both companies have their better and worse overclockers. You guys continue to ignore the fact that many 4870's are hitting 820-830MHz. 4850's are clocking to the moon for many people from their factory 625MHz.
Yep, that's the rumor, which again, has been circulating for months in these various Super RV770/RV790/40nm 4995 threads. Again, not saying its impossible, I just think its highly unlikely we'll see both additional SP/TMUs and higher clockspeeds on a 55nm process given the limitations we're seeing with RV770 and the 4870.From what I understand AMD has extra shaders and TMU's built into the RV770 for redundancy, to make sure they get yields. If they're process has matured to the point that they're finding that they're getting a decent number of chips that can run well beyond 750MHz with everything built in working, it make sense to sell it. It's silicon they're already producing. They're only hurting their margins by slowing it down and disabling parts to sell it at a lower cost for a lower binned part (4870). Think about it, if that's the case, they're going to charge more for the exact same silicon they're already producing.
I'd love to find out, maybe then we'll actually get some confirmation that a 13% core clock increase results in ~13% increase in performance. Until then I guess we can just assume we'll see similar linear scaling to the 10% overclocks that seem to be the limit on actual 4870s.Mean while, you guys can keep telling me AMD video card products have no headroom, I'm going back to playing AoC on my 820MHz 4870 with 4600MHz memory. Maybe one of these days I'll decide to have my fan make a little noise (I'm still set to auto - 27%) and crank it up to the speed I find bearable, which is around 44% and see what I can get.
Originally posted by: SlowSpyder
Why would performance not scale with clock speed?
I did the same thing a few days ago, it hasn't arrived yet. I started getting buyers remorse but then I remembered EVGA has the 90 day step-up thing, so I hope these will drive down the price of the GTX 285/295's to the point I can upgrade to them.
Originally posted by: chizow
So tell us all, how does a 4870 perform when overclocked 10-13%? You can hit 830MHz at stock volts, lets see what you get with water cooling and a voltage increase, should hit 850MHz easy right? I mean that's what the RV790 is supposed to be, you should be able to get that extra 20MHz np given how well ATI parts have overclocked all these years.
So again, do you think the same conclusion would be accurate when comparing the 4850 and 4870? The difference between the cores is clockspeed, yet based on that AT analysis, it would lead you to the same conclusion that the RV770 is less efficient per mm^2 than the RV770....Again, its obvious RV770 is less power efficient compared to GT200 and any efficiency comparison based on die size also goes away once you account for clockspeed differences (again compare GTX 280 to 4850 or GTX 285 FTW to 4870).
Idle temps in the 50s-60s with load temps, even overclocked in the 70s-80s. Those results are consistent throughout the thread I linked. The HardOCP link uses their own infrared thermometer which by itself doesn't tell us much if we don't know relative temps for the software diode readings.
Uh, Furmark? Try renaming to FUDMark and see if you're still stable once the test is actually running full speed.Originally posted by: thilan29
If I could get the FC2 benchmark (unfortunately the only consistent gaming benchmark I have) to work in Win7 64-bit I would show you but things are a bit funky since I went from Win7 32 to 64. Yeah I already hit 850 easily at 1.3v. I just tried right now and it hit 880 @ 1.35v and it didn't crash in Furmark. http://i53.photobucket.com/alb...thilan29/stability.png If I get things sorted with Win7 64 I'll post back what I get with the FC2 benchmark and try for 900MHz.
And what does that have to do with the 4850 and 4870 resulting in exactly the same flawed conclusion when you don't account for clockspeed when using die size as some gauge of efficiency? Also direct comparisons to power efficiency are still relevant and even though Nvidia's shaders run at 2x or more, they still draw less power and get as much or more work done.See it's more complicated than that...the shaders run at a different speed to the core for the nV cards (sometimes double the speed of the shaders on the ATI cards). This is why I don't think you can make direct comparisons about efficiency....it's a different architecture. As I said before that comparison wasn't great but it was the only one like that I could find. Disregarding that...do you have a comparison taking core/shader/mem bandwidth into consideration and calculating efficiency instead of just your opinion?
They don't distinguish which temps were used, but regardless, 90C under load overclocked 100MHz to 700MHz (16.67%) with stock fan speed of 29% is certainly much, much better than the 4850 and 4870s which were idling at stock speeds at those temperatures lol. :laugh:"To measure the temperature on the GeForce 8800 GT based video cards we used NVIDIA?s NV Monitor for the internal GPU temperature"
So they were the actual GPU temps and they were all in the 90C range up to 95C.
Originally posted by: nyker96
i think that it does 20-30% more is the reason why it's not 49xx but 48xx. I would personally expect a 49xx series to be about at least 50% faster than previous model series.
Originally posted by: chizow
Uh, Furmark? Try renaming to FUDMark and see if you're still stable once the test is actually running full speed.
Also direct comparisons to power efficiency are still relevant and even though Nvidia's shaders run at 2x or more, they still draw less power and get as much or more work done.
The GTX 260 draws less power and performs similarly to the 4870 despite being larger chip on a larger process with more transistors.
They don't distinguish which temps were used, but regardless, 90C under load overclocked 100MHz to 700MHz (16.67%) with stock fan speed of 29% is certainly much, much better than the 4850 and 4870s which were idling at stock speeds at those temperatures lol. :laugh:
So 28s of Fudmark now counts as stable? Its not even long enough to heat the GPU up. Again, its a good start, but clearly a bit optimistic given it takes much higher volts and water cooling to attempt speeds expected from an air-cooled 4890 at 850MHz on the same 55nm process as the 4870.Originally posted by: thilan29
I edited the original link with another screenshot of it after I renamed it to Fudmark.exe. Still ran stable.
Again, you're the one who pointed to the flawed AT efficiency comparison, but as has been shown time and time again, AT chips have historically proven to be inefficient, power hungry, and leaky, requiring additional power and clock cycles to be competitive on the high-end leaving very little headroom for additional overclocking. I've already provided numerous links detailing this over the years backed by historical fact with specific parts.This is my point...the shaders themselves are different to begin with (along with mostly everything else) so how can you compare them and say without a doubt that one is more efficient than the other (unless you actually have intimate knowledge of the architectures)? (ie. if 2 cards were identical except for power draw such as the 260 55nm vs 65nm, THEN you can say one is more efficient than the other)
Again, going by the AT link you provided, the GT200 provides more performance per watt and that's even with the disadvantage of being on a larger process. The 260 draws slightly less power at load and signifiicantly less power at idle, and again, that's on a 65nm process. While GT200b B2 didn't result in any significant power decreases, that clearly changes with B3 as there GTX 285 draws less power than GTX 280 and GTX 295 draws significantly less power 4870X2, yet both the 285 and 295 are faster than their counterparts.Actually the 260 65nm draws as much power as a 4870 (has been discussed and linked to before so I'm not gonna do it again) and they perform similarly so going by that metric they have the same efficiency, although they use very different means to get there (and actually if you just look at the amount of transistors...the 260 should be much faster than the 4870 but it's obviously an ill-informed conclusion). Again though, claiming one architecture is more efficient is a shot in the dark since the GPU designs are VERY different.
4850 Temp discussions
Originally posted by: chizow
So 28s of Fudmark now counts as stable? Its not even long enough to heat the GPU up. Again, its a good start, but clearly a bit optimistic given it takes much higher volts and water cooling to attempt speeds expected from an air-cooled 4890 at 850MHz on the same 55nm process as the 4870.
Again, going by the AT link you provided, the GT200 provides more performance per watt and that's even with the disadvantage of being on a larger process. The 260 draws slightly less power at load and signifiicantly less power at idle, and again, that's on a 65nm process.
Again, the stock profile/bios and fan speed issues on both the 4850 and 4870 were clearly an issue at launch, so much so that people were forced to flash their BIOS or look at 3rd party coolers to fix the problem. I guess at some point ATI finally allowed fan control in the driver or through ATT, but the temp issues were certainly a black eye on the 4800s launch.
Erm, no. My 4850 idled at ~75 c, and load temperatures didn't get much higher because the fan revved up.Originally posted by: chizow
They don't distinguish which temps were used, but regardless, 90C under load overclocked 100MHz to 700MHz (16.67%) with stock fan speed of 29% is certainly much, much better than the 4850 and 4870s which were idling at stock speeds at those temperatures lol. :laugh:
Please link to a single post in that thread that shows a 4850 is idling at 90C (or higher) at stock clocks. Thanks.4850 Temp discussions
Lookin good on that 4890, thanks for testing. I guess we'll have to agree to disagree on the rest and see what happens with this latest rumor of a faster RV770.Originally posted by: thilan29
My VRM cooling is not adequate at those volts speeds...
:laugh:Originally posted by: Paratus
The way you're meant to be played!
Originally posted by: chizow
Lookin good on that 4890, thanks for testing. I guess we'll have to agree to disagree on the rest and see what happens with this latest rumor of a faster RV770.Originally posted by: thilan29
My VRM cooling is not adequate at those volts speeds...
Perhaps your case has better cooling than the average PC? As for not having to touch the BIOS or use third party tools, you do realize the launch fan problems were fixed in later editions and driver updates right? Hence the need for people to flash their BIOS to begin with.Originally posted by: BFG10K
Erm, no. My 4850 idled at ~75 c, and load temperatures didn't get much higher because the fan revved up.Originally posted by: chizow
They don't distinguish which temps were used, but regardless, 90C under load overclocked 100MHz to 700MHz (16.67%) with stock fan speed of 29% is certainly much, much better than the 4850 and 4870s which were idling at stock speeds at those temperatures lol. :laugh:
I never touched the BIOS or used third party utilities or fan controls.
The fact is, if a 4850 is idling at 90 C at stock, that?s abnormal. But given you haven't used a ATi card since the 9700 Pro, I wouldn't expect you to be able to contribute with first-hand experience, so you wouldn?t know this.
Please link to a single post in that thread that shows a 4850 is idling at 90C (or higher) at stock clocks. Thanks.4850 Temp discussions
Originally posted by: flizesh
Hello,
I built a new PC around September of last year and got the VGA SAPPHIRE 100242L HD4850 512M RT from Newegg. I know the card runs hot, but here 6 months later I find the idle temp on my card going higher and higher.
First it started idling at 80C, which I was fine with, I know the card runs hot. But progressively the idle temp kept going up, 81, 82, 83, etc and now the card is idling at 85-86C after 6 months; while I am just in Windows, not even playing any games.
I opened the case and checked for dust on the fan etc, and found almost no dust or anything like this so I don't think that is the problem.
Is my card defective, and if not why does my idle temp keep going up over time?
Thanks for any help and advice.
Originally posted by: dakels
Oh wow I am having the exact same problem and you were writing your post as I was writing mine. Anyways mine was around 80C at 80% fan speed (too loud) under load. Now its about 100C at 80% fan speed and 90C at 100% fan speed. I'm also starting to get random shutoffs too which makes me want to try RMAing this card. I have no noticeable dust on my card either and my case is clean due to dust filters on my case intake fans. I am thinking that it's possible that the thermal adhesives are starting to wear down? It might be necessary for me to reapply thermal grease but I really don't want to. With that effort I'd rather be putting in a third party cooler. I shouldn't have to do this for normal operation of this product so therefore I think I can RMA it. Hopefully get one with a better cooler too, non reference like mine.
Originally posted by: novasatori
I just RMA'd 2 Sapphire 4850 512s with the reference cooler to newegg for a refund, it got so bad since I got em in July that the cards were peaking at 103C and throttling at 100% load with the default fan profile, and even switching to 100% fan speed they'd creep up to 103C after long enough time.
Both cards were in diff computers, same specs(Cases are Antec 900 with all fans on max, CPUs idling at 18C (Q6600@3.6ghz)), and there was no visible dust, so yeah, the reference cooler has issues imo.
edit:
Sapphire cards RMA to retailer, like I went to newegg cause newegg gives em a 1yr warranty, if you go to sapphire they will charge you a $15 admin fee
Worked out ok for me as I got the retail price I pay refunded since the card was discontinued heh.
Originally posted by: Butterbean
I have same prob - my 4850 (Visiontek) idle temps (@ default) went from 80 - 82 to 86 - 88. I guess I'll have to finally get the Accelero on ( thats been in my drawer for 3 months)
Originally posted by: fijianalky86
i may go with this card after its first "BIG" driver update
....i had a TERRIBLE problem with the x1950 pro (my only ATI attempt) but i was very happy with the performance and IQ until it F*d up a few hours after....i really wanna like these 4*** series cards! ,will see how it goes
You know what they say...those who live in glass houses.....
It wasn't a fan problem as much as it was a problem with the card staying at 3D clocks when idling. Mine did the same, and it was reporting 74C idle. Had it dropped to 2D clocks, it would have been much lower than 74C.Originally posted by: chizow
As for not having to touch the BIOS or use third party tools, you do realize the launch fan problems were fixed in later editions and driver updates right? Hence the need for people to flash their BIOS to begin with.
You made the claims, so the burden of proof is with you. I skimmed the thread you linked and couldn't find anyone claiming 90C idle temps. The fact is, even if they were, 90C idle is abnormal for either card:As for relevant info, I'm not going to dig through that thread or go back to launch, if you're that interested feel free to search between 6/20 and 7/10 or so, the weeks around 4850's launch.
But progressively the idle temp kept going up, 81, 82, 83, etc and now the card is idling at 85-86C after 6 months; while I am just in Windows, not even playing any games.
[/quote]I have same prob - my 4850 (Visiontek) idle temps (@ default) went from 80 - 82 to 86 - 88. I guess I'll have to finally get the Accelero on ( thats been in my drawer for 3 months)
Anyways mine was around 80C at 80% fan speed (too loud) under load. Now its about 100C at 80% fan speed and 90C at 100% fan speed.
Those are load temps; you were talking about idle temps. You need to retract your claims.I just RMA'd 2 Sapphire 4850 512s with the reference cooler to newegg for a refund, it got so bad since I got em in July that the cards were peaking at 103C and throttling at 100% load with the default fan profile, and even switching to 100% fan speed they'd creep up to 103C after long enough time.
Idle temp is 62C and it goes up to 105 in no time.
The guy on the phone that handles the RMA's knew about the problem.