Radeon HD 7950 Owner's Thread

[Rvenger]

Hi All,

I had a chance to overclock mine today. So far I was able to run 1000 core/ 1375 memory at stock voltage. If I raised to 1050, it would crash in 3dmark 11. I kicked up the core voltage to 1.06v and it stopped crashing. I do have a question though. I replaced my power supply and the leads to the 8 + 6pin connector are tied off together on the same cable. If I ran 2 separate cables, is it possible it might make my card more stable? My ASIC quality is 87.9% but I might have a bum overclocker unfortunately.

 

[Fire&Blood]

Hi All,

I had a chance to overclock mine today. So far I was able to run 1000 core/ 1375 memory at stock voltage. If I raised to 1050, it would crash in 3dmark 11. I kicked up the core voltage to 1.06v and it stopped crashing. I do have a question though. I replaced my power supply and the leads to the 8 + 6pin connector are tied off together on the same cable. If I ran 2 separate cables, is it possible it might make my card more stable? My ASIC quality is 87.9% but I might have a bum overclocker unfortunately.

Ideally you want separate cables but it doesn't warrant a upgrade if you are looking at a PSU of same ratings. I very much doubt an equal PSU with separate cables would allow you to clock it further than you do.

It may not be a bum. ~1.25v is the voltage most need for higher clocks, if you can't get past 1150 then it may qualify as a bum overclocker. 1025 on stock voltage without heat issues is considered good unless your card undervolts in which case the numbers thrown around are irrelevant to you.

Mine is somewhere in OH right now, got it on Amazon, canceled NCIX order as it won't be in until 8-14.

 

[RussianSensation]

Hi All,

I had a chance to overclock mine today. So far I was able to run 1000 core/ 1375 memory at stock voltage. If I raised to 1050, it would crash in 3dmark 11. I kicked up the core voltage to 1.06v and it stopped crashing. I do have a question though. I replaced my power supply and the leads to the 8 + 6pin connector are tied off together on the same cable. If I ran 2 separate cables, is it possible it might make my card more stable? My ASIC quality is 87.9% but I might have a bum overclocker unfortunately.

Stop being a girl and overclock her. Stock voltage on HD7970 is 1.174-1.175V. You got so much room. Put her up to 1.12-1.13V. My card only has ASIC of 71% and does 1150mhz on 1.174V. Voltage is the answer.

Download HWInfo64 to help you monitor VRM temperatures, GPU temps and voltages.

The leads of 6+8 on the same cable shouldn't make any difference. I am powering the 7970 off 1 cable and the PSU is 5 years old. You can try 2 cables if you are bored. However, 1.06V is extremely low and the fact that it can do 1050mhz at such low voltage is amazing, not a dud. The reference 7950 voltage is 1.093V, and you aren't even there yet. AMD lowered it because the stock 7950 only runs at 800mhz. 100% safe voltage is 1.175V since HD7950 and 7970 is the exact same silicon.

 

[Rvenger]

ahh ok, so I should be able to get to 1100mhz no issues. How far do you think the memory can go without issue?

 

[Rvenger]

1100/1377 P9006

8858 Graphics score. Not bad.

 

[Fire&Blood]

8858

Is that your WEI score?

 

[Rvenger]

Is that your WEI score?

No lol. Ok for 1100 core it seems stable at 1.11v. RS, I apologize, this is actually the first time I overclocked a graphics card since the Nvidia FX5900 days.

 

[Fire&Blood]

What kind of temps were you getting at 1100 under load?
My case is far from good ventilation, just trying to gauge what I can expect come Wednesday.

 

[3DVagabond]

Hi All,

I had a chance to overclock mine today. So far I was able to run 1000 core/ 1375 memory at stock voltage. If I raised to 1050, it would crash in 3dmark 11. I kicked up the core voltage to 1.06v and it stopped crashing. I do have a question though. I replaced my power supply and the leads to the 8 + 6pin connector are tied off together on the same cable. If I ran 2 separate cables, is it possible it might make my card more stable? My ASIC quality is 87.9% but I might have a bum overclocker unfortunately.

You have an NZXT PSU. It has a single 12v rail. It will improve nothing to use separate cables. They all come from the same, one, rail, anyway.

 

[Alusan]

What kind of temps were you getting at 1100 under load?
My case is far from good ventilation, just trying to gauge what I can expect come Wednesday.

I'm curious about this too. I have the Sapphire 950MHz edition (ASIC 89.6%) which seems to have a similar heatsink to the Twin Frozrs and I was able to do 1050/1650 at the stock 1.031V and 1125/1700 at 1.093V. I tested with the Crysis demo which is pretty good about crashing, and then played through Trine 2. My card seems like a great clocker and I'd like to take it further, but @1.093V it gets past 80C in Trine 2 and the monitor loses signal eventually. I know my case is at fault cause taking off the side panel lowers temps to 75C max, but that still seems a bit hotter than what people have been reporting. Can't complain about an easy 40% overclock from the stock 7950 though.

Fan's running over 80% to keep these temps but it's really not that bad. I had a 7870 Hawk before this card and unfortunately the Twin Frozr was pretty loud for me even at 50%. Russian, how cool is your 7970@1150? I'm debating whether I should reseat the cooler with some new TIM because that did lower the temps of my 7870 by ~3-4C.

I'm also wondering if setting too high a memory clock can end up damaging the GDDR5. My card looks like it could go past 1700MHz but I'm not sure it's needed and there aren't temp sensors for the memory on this Sapphire card either.

 

[Fire&Blood]

I'm curious about this too. I have the Sapphire 950MHz edition (ASIC 89.6%) which seems to have a similar heatsink to the Twin Frozrs and I was able to do 1050/1650 at the stock 1.031V and 1125/1700 at 1.093V. I tested with the Crysis demo which is pretty good about crashing, and then played through Trine 2. My card seems like a great clocker and I'd like to take it further, but @1.093V it gets past 80C in Trine 2 and the monitor loses signal eventually. I know my case is at fault cause taking off the side panel lowers temps to 75C max, but that still seems a bit hotter than what people have been reporting. Can't complain about an easy 40% overclock from the stock 7950 though.

Fan's running over 80% to keep these temps but it's really not that bad. I had a 7870 Hawk before this card and unfortunately the Twin Frozr was pretty loud for me even at 50%. Russian, how cool is your 7970@1150? I'm debating whether I should reseat the cooler with some new TIM because that did lower the temps of my 7870 by ~3-4C.

I'm also wondering if setting too high a memory clock can end up damaging the GDDR5. My card looks like it could go past 1700MHz but I'm not sure it's needed and there aren't temp sensors for the memory on this Sapphire card either.

I think you are pushing the memory too far. Even if clocking the memory that high doesn't cause crashes/freezing, error correcting will negate additional gains. I would stick with more conservative values for the memory, say 1570-1600. Even if 1200 or more is doable at 1.125v in a case with great push-pull configuration, I wouldn't try it on air.

I'm curious if my case will allow for 1050/1550 as a permanent setting with reasonable temps and less than 70% fan setting.

 

[Rvenger]

What kind of temps were you getting at 1100 under load?
My case is far from good ventilation, just trying to gauge what I can expect come Wednesday.

Peaked at 70c but my ambients were high from stress testing all day.

 

[Fire&Blood]

That's impressive. Can't wait til Wednesday, I'll be a happy camper if I can get similar temps @ 1050/1500.

 

[Rvenger]

I can run 1000/1375 on the standard 1.035v. I am very happy with the performance of this card.

 

[Rvenger]

You have an NZXT PSU. It has a single 12v rail. It will improve nothing to use separate cables. They all come from the same, one, rail, anyway.

I know that, I just thought using separate cables would provide cleaner power to the card. 200w distributed to 2 cables is better than 200w all in one cable. Not sure how much 18 guage wire can handle but I don't think it will affect anything since I am stable at 1100.

 

[Fire&Blood]

I know that, I just thought using separate cables would provide cleaner power to the card. 200w distributed to 2 cables is better than 200w all in one cable. Not sure how much 18 guage wire can handle but I don't think it will affect anything since I am stable at 1100.

I would worry about that with the 590, 690 or 6990 but power requirements for those demand PSU's that have separate rails anyway. Not an issue with 7950.

 

[philipma1957]

this is a silly good card. I did a small oc 880 = 920 1250 = 1300


I can run the fans at 1300 rpm. Quiet and cool running a bluray. For what little gaming I do it is also good.


this card really works well with a 1080p screen.

When I do visual comparisons to the hd6870 and the hd7750 every movie and dvd is sharper movements are look better.

I can't believe how quiet this card is at low fan speeds.

 

[Alusan]

I think you are pushing the memory too far. Even if clocking the memory that high doesn't cause crashes/freezing, error correcting will negate additional gains. I would stick with more conservative values for the memory, say 1570-1600. Even if 1200 or more is doable at 1.125v in a case with great push-pull configuration, I wouldn't try it on air.

I'm curious if my case will allow for 1050/1550 as a permanent setting with reasonable temps and less than 70% fan setting.

I did runarounds in games at different memory settings but performance was still improved at 1700. Granted it's barely noticeable so there's not much point in pushing it any farther. I think the 7800s need the extra bandwidth more but I couldn't get my 7870 memory nearly that high.

If you can hit those clocks on your stock voltage you should be good to go. I didn't test extensively but it seemed liked my stock voltage overclock didn't raise temps too much.

 

[Rvenger]

Alusan, Did you raise the mem voltage at all?

 

[Alusan]

Nah, it's been at 1.6V. I also used Trixx to overclock because Afterburner would give me weird flickering as soon as I made any changes with it.

I think I'll run some Metro benchmarks later today to see how much of an effect the increased bandwidth gives.

 

[3DVagabond]

I would worry about that with the 590, 690 or 6990 but power requirements for those demand PSU's that have separate rails anyway. Not an issue with 7950.

Nothing wrong with separate rails. Separate rails are actually safer. It's just cheap PSU's that are the problem. No issues with a good Antec or Enermax PSU that have the multiple 12v rails.

 

[thujone]

yeah... and newer power supplies are coming back around to using just 1 rail. really it's just all about the build quality and amps on the 12v rail.

 

[Rvenger]

With the new drivers this card runs super smooth. I was thinking about picking up another 7950 but to my surprise bf3 now runs excellent on the 12.8 betas. Just as well as my 680 on the same settings. So at this point in time i will just run a single card until somethng comes out thats more demanding.

 

[Alusan]

So I did some runs of the Metro 2033 bench at Very High, 4XMSAA, 16XAF, and DOF and PhysX disabled. 5 runs at each setting and the fps is the average that the benchmark results reported. Side panel was off to help with temps until I get some more fans tomorrow.

https://docs.google.com/spreadsheet/ccc?key=0Atpt9vZWXf9HdGZMZmp6LVhLVGtKcGlmUVpKZkwxSVE

What I ended up finding from this is that increasing just the core clock by 18% gave me a 12% increase in fps @1920x1200 and an 11% increase in fps @2304x1440. Increasing the memory clock by 36% gave me a 7% increase in fps at both resolutions.

With both the core and memory overclocked, I got a 21% increase in fps @1920x1200 and a 22% increase @2304x1440. I kind of expected the increased memory bandwidth to have more of an effect at the higher resolution than the lower, but that doesn't seem to be the case in this benchmark.

These aren't the highest temps I recorded though-with the overclock, Trine 2 peaked at 77C and the VRMs at 100C (!). I've seen people say they're fine at even 120C, not sure how true that is.

With the new drivers this card runs super smooth. I was thinking about picking up another 7950 but to my surprise bf3 now runs excellent on the 12.8 betas. Just as well as my 680 on the same settings. So at this point in time i will just run a single card until somethng comes out thats more demanding.

Yeah, latest drivers have been excellent compared to the earlier ones on my 7870, both in terms of performance and stability. I still get occasional flashes on the desktop that I think has something to do with the memory switching from idle to load. Does anyone else get these? I had it on my unoverclocked 7870 too, but not my 6870 using the same drivers.

 

[joe_H]

Need some help with temps. Decided that I wanted to upgrade my monitors to the Achieva Shimians. Figured my old Sapphire 5850 wasn't going to cut 1440p, so I picked this card up.

Hooked everything up, loaded 12.7 beta drivers. Was a little surprised to see that my card was idling at approx 52C. Did some searching and found that apparently multi-monitor setups cause the video card to idle higher. Disconnected one of the Shimians, and the idle temp dropped to around 39C. Much better. Whether I run single or dual monitor, the load temps get around 71C. Ambient is approximately 79F.

I've seen a few posts which state idling in the 50C range is bad for the card. My case is an Antec1200, so I added a side 120mm fan to see if temps changed. Made almost no effect. Tried the fan both directions, and actually have 1-2C lower temps sucking hot air out, rather than blowing air in.

I did try a brief stint at overclocking. Upped the stock 880/1250 to 1000/1400 on stock voltage, and raised the fans to 70%. Load temps were around the same, low 70s.

I guess my question is there anyway to lower the idle temps, or should I even bother? Will idling in the 50s harm the card?