Belial's Comprehensive Guide to 7950s!

[Belial88]

Been playing with an Asus 7950, it's a new revision as it comes shipped with BIOS 105. I've got some sad news people:

* Can't be changed to BIOS 101 or 104.
* Comes with Elipda 60F
* VOLTAGE LOCKED

Quite sad...

I did some testing with it's stock voltage of 1.09v, and I got to 56C in a ~10C room. So it'd be more like 66-70C if you add a 10-14c delta on that, at minimum, as room temp is ~22C. That's with 100% fan speed with +50 power limit fix. So put it to 1.15v that I normally test these cards on, and that's more like 75C max load temp at room temp with 100% fan speed an +50 power limit fix.

So even the Asus model overheats on stock voltage at 100% fan speed. That said, I was quite impressed with the cooler, as far as they go - the 100mm fans are far quieter than 92mm and especially 75mm models, and even at the same dBa are far less annoying because they aren't as high pitched jet engine squeeling. It's about 10C cooler than the Gigabyte WF3, and 5C cooler than the Dual-X model.

And I'm really quite astounded by the black PCB and build quality, it's a lot better than even the Twin Frozr 3. Really I should have bought this model from the start, rather than the gigabyte - significantly better VRM (temps wayyy lower on VRM on asus vs gigabyte), black painted PCB is better than the blue-fab pcb, just better SMD components used.

 

[Belial88]

Here's throttling at +20%. This is 100% fan speed in a 10C room, so the card should actually be using much less power than in normal usage, at 950mhz@1.09v, which is much lower than most cards at stock. Literally, throttling at stock settings on +20.

Pretty straightforward. OCCT Error test shader 7, no fps limit, 2000MB Memory to Test. Easy to find if you test properly, unlike using games.

You can see the fps is 108, and my clock is 810mhz on the right. There's also a GPU clock graph on the bottom right side, and you can see the clocks going up and down, though it's mostly staying down.

And here's +50 on 950mhz@1.09v. As you can see, there is a MASSIVE difference between +20 and +50, my FPS jumped 18% by going to +50 from +20. You can see the GPU clocks graph on the bottom, showing the throttling of the +20 compared to how it should look, at +50.

Anyone can simulate this proper test to find throttling, which is even heavier if you use a higher clock, voltage, lower fan speeds, or aren't in a 10C/50F winter room.

I apologize I could not provide these results sooner, my 7950s were a bit tied up, but I expect multiple apologies anytime now.

 

[Fastx]

Edit Decided to withdraw my post response on my opinion/rambling on about OCCT.

 

[KingFatty]

Can you quickly remind me how to get +50% power? Is that some kind of registry tweak, or edit an .INI file, or perhaps a utility is doing that?

 

[Fastx]

Can you quickly remind me how to get +50% power? Is that some kind of registry tweak, or edit an .INI file, or perhaps a utility is doing that?

KF here you go from Belial first post at the bottom. http://forums.overclockers.co.uk/showthread.php?t=18509458

KF you might want to also read IEC comments in post #71 fwiw in this thread regarding +50 and cooling under his last screen shot in that post.

 

[KingFatty]

Belial,

Do you need any additional information on the Powercolor PCS+ 7950 to supplement the guide? I managed to snag one of the $149 pre-black-friday specials and now have a tracking number, so I think it won't be canceled and I'll be able to test it etc., but it looks like you already have all the info filled out for that card?

Looks like a lot of reading ahead of me, gotta go back through all of the posts in this thread as I didn't expect to own a 7950, but I enjoy pushing the cards to see what they can do, looking forward to doing the +50% and I really appreciate all the work and attention you put in to this.

 

[Belial88]

If you see any info that's wrong, I'd love to be corrected. Any more detail on the PCB would be appreciated.

Powercolor PCS+ is a fine choice, the problem with it is that it's usually much more expensive than the other models so it's never recommended, it lacks VRAM voltage control so it's not a 'perfect' 7950, and sometimes it ships with Elpidas, which is a big problem since you can't identify whether it's Elpida or Hynix model like you can with other models (ie MSI use different pcb/power inputs, WF3 has different power inputs). It's not a perfect choice, but there is nothing glaringly wrong with the card and I'd really say it's a solid 'above average' model in general.

And getting it for $150 is absolutely insane, that's awesome. Even a reference model at 150 would be a steal, let alone a solidly good model. So that's what really makes your choice super smart and awesome

 

[Mcdovin]

Beautiful guide.

I have an HIS 7950 ref. model I believe
http://www.newegg.ca/Product/Product...82E16814161400

and I was wondering if getting 86-87*C in a game like Far Cry 4 was okay, with everything except AA maxed?

I ran Furmark for about 3 minutes at a 1000mhz core OC and it went up to 87*C which worried me. Should I go with an aftermarket cooler like an AC one, can I get a different model 7950 like an ASUS one or should I just wait and get a GTX 970 or similar when I have the cash?

I could buy a 7970 for about 130-150 off Kijiji here in Edmonton, but I've also heard if you CF 7950's they actually beat a single 970 in most situations and it only costs sub 150 to get another one.

Other than the temps and noise of fan, I love the card and it's a big upgrade from my old GT 640 and 6870.

Thanks and hopefully you guys can help me out.