Need help! GPU usage stutters on Sapphire 7950 Boost edition
 

I need help guys. I just bought a Sapphire Dual X 7950 Boost edition yesterday and i immediately noticed on afterburner that GPU usage keeps on fluctuating whenever i'm gaming and benchmarking with 3dmark vantage, 3dmark 11 and heaven dx11. It couldnt stay in a specific percentage (%).

http://img266.imageshack.us/img266/7439/helpyd.png

I was wondering if this was normal for the boost edition of the 7950 because if it is not, i'll replace the card immediately.

My specs are
Motherboard: Gigabyte M68MT-S2
Processor: AMD Phenom(tm) II X4 965 Processor @Stock 3.4Ghz
Videocard: Sapphire DualX 7950 Boost edition @Stock 850 core, 925 boost; 1250 memory clock
Ram: Kingston 4gb (2pcs 2gb)
HDD: Seagate 1Tb

Operating System: Windows 7 Professional, 64 bit
Driver: Catalyst 12.11

Looks like the card is throttling, usually because of overheating or your PSU is underpowered.

The max GPU temp was 65C so we take that out of the equation.

I posted this on other forums as well and someone said that i should turn up my power control settings to 20%. and when i played crysis, it went stable.

http://img228.imageshack.us/img228/9...owerslider.png

Question is, is it safe to let it stay at +20% power control settings? Or is it considered as "overclocking" already?

It shouldent need that 20% slider at stock speeds,try playing crysis with every thing on stock,also your using an outdate version of afterburner and it dosent seem to 100% support your card:
http://event.msi.com/vga/afterburner/download.htm

alright ill go download the latest right away :) This was when i didn't apply +20 power control settings.

http://img827.imageshack.us/img827/4408/help2s.png

I am using +20% slide since day one on my non-GHz edition XFX 7970. The card runs fine like that for 10 months now. Normally you should not need the 20% for everyday situations but it obviously exists for a reason, and that is to solve an issue like yours.

Ohh, i'll just leave it at +20% then. THANKS GUYS! :)

This could be because your card is factory OCed.

AI AI AI!!!


This is how boost cards work. It raises clock when card is drawing less power than TDP. Clock goes up, power draw increases, boost is dropped.

Increasing power limits...of course that levels it out.


you card probably shouldn't have been a boost card. To fix that properly, you probably need to run lower voltage.


If your card has secondary BIOS, you might want to consider trying a non-boost BIOS. All of my non-boost cards do the same with boost BIOS, but boost BIOS gives my cards 1.25 V instead of the 0.9875 V they get with stock BIOS.

In that case, he might as well return the card.
Since the card isn't functioning as intended. The end user should never need to do anything to the card to run at factory OCs.

My card does the same thing with the Boost BIOS. It has to be set to +20% out of the box or it performs worse than my 6950 did.

The case is that this "boost" feature on 7950 behaves like that. Reviewers have well documented the fact.

http://img.techpowerup.org/130105/7950BClockspeed.png

anandtech.com review

You are right, and by doing nothing, this is what boost cards do, and it's NOT a problem.

Just how they work.


The stock for 7950 is 800 MHz, and the boost cards get 850MHZ, with boost up to 925 MHz.

This is faster than 800 MHz cards, but slower than 900 MHz non-boost cards(Gigabyte and XFX).

While boost cards (both AMD and Nvidia) DO indeed exhibit a lot of up and down usage, I've never seen one's GPU usage show up as even and consistent peaks and dips like that, so it does seem odd.

Typically a GPU usage chart for a boosted GPU looks like a variable roller coaster, as most games have a varying amount of load, not specific peaks and dips like that.

Even if the voltage were a two tier stepped affair vs variable, you wouldn't see that kind of usage with the same peaks and dips throughout the chart, because the usage is more dependent on the load the game puts on it than the voltage used.

My Sapphire Dual X 7970 has a tiny two position switch on the PCB near the expansion plate, designated by 1 & 2 printed on the back of the PCB. If yours has one, I would try setting it in the non OCed (1) BIOS, then check how the usage chart looks. Completely shut down the system before changing the switch position.

I'm not sure, but I'm guessing these cards are designed so BIOS position 1 just runs it at reference speed without the boost throttling. If so, it's conceivable that manually OCing while in the BIOS 1 position would render no severe up and down throttling, which in some cases might smooth frame rates. It's worth a try anyway.

I would first test your ASIC quality with GPU-Z (right click upper left icon on GUI) to get an idea how much leakage your GPU has. It's not always the case, but often times a low ASIC quality (less than 70 for instance) means less OCing ability on air. If you try manually OCing from the BIOS 1 position, I would start with no more than BIOS 2 core and VRAM speed.

The chart you have shows the usual pattern.
The problem is that the card the OP has fluctuate a lot more than usual. That is whats curious.

There are parts of the chart where the card down clocks much under 850Mhz and also the usage plummets to the 20ish%.
My friend has a Sapphire 7950 Dual-X Boost also, and it does not fluctuate as badly as the OPs it seems.

Ok. Boost sucks. I bought my first 7950 that started at the original 800mhz no boost. That was all good, overclocked well and didnt fluctuate fps or voltage. Then i decided to crossfire it with another and the only thing i could get was a boost edition.

So.... I flashed my original card with a boost edition bios so they would be in sync. What a mistake. Fps were all over the shop in crossfire mode! Not to mention voltage. I found that if i put 20% on them it seemed to fix the fluctuation alot at stock speeds (850-925) but when i overclocked them beyond those speeds it would just go silly again on the fps and voltage (monitored through AB).

Fix.... I found a bios that was an original 800mhz XFX one that worked on both cards!
Overclocks well, no need to put 20% and no fluctiation on fps or voltage in crossfire mode. This will also work with just one card coz i had no issues with my original 800mhz non boost edition.

It took me a while to find a bios that was compatible for both cards but i didi it.

Cheers. Hope this helps coz it helped me! All the best. ;)

I've been tempted to run my 7970 Dual X in the BIOS 1 position which is 950 MHz and run a manual OC on it to see if it is more stable.

If usage drops and clocks drop, the scene is probably loading. ;) it only does it twice in the OP.