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7950 Crossfire Usage issues..

After much fiddling I have completely fixed the usage issue using a pair of 79xx cards.

Windows 8 is the problem. No matter what I do the usage in windows 8 is crap and jumping all over the place. No matter which drivers it still does it.

Completely fresh install of Win 7 complete and the latest beta drivers installed and I'm seeing over %95 usage constant in everything including furmark on both cards. The sudden dips as per my video no longer happen and games are perfectly smooth and the benefits of a second card really show.

It's weird going back to Win 7 but strangely it feels like a breath of fresh air compared to the bloated feel of Win 8.
 
Ok so it's not windows as I'm now getting the same problem again but on a single card. The clock speed is jumping between 800 and 925 almost constantly during use at stock settings. Setting the power bar to +20 makes no difference. This is causing stuttering and jerkiness in game.

After a good read it seems the problem is the boost bios. The simple fix is to re-flash with the stock bios but it seems the newer HIS iceq cannot be flashed even though they have a dual bios. Apparently the card after flashed will just not display as there is a hardware lock in place. I'm also not willing to try this on a few days old card that should work out of the box.

So it seems HIS are selling cards with a borked boost bios that causes very noticeable performance issues and have decided to not allow people a simple flash to stock to fix.

Both these cards are being returned I have had enough now. One is faulty the other is not fit for use so will DSR.
 
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LtMatt said:
Sorry to hear that Moog. Good feedback about the His cards though that we can pass on to potential buyers. What was the exact model name again?
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HIS 7950 ICEQ BOOST H795QC3G2M

I have not tried to flash the bios so cannot confirm if the bios can be flashed or not.
 
GTX 680 plugged back in and everything is as smooth as butter with a constant 1280 on the core. Not having the core jump about makes such a difference.

It seems AMD released the boost bios to just get the numbers up on the 7950 to compete with the 670.

The max it can achieve is high but the card fires a lot of voltage at the core to do it which then causes it to throttle back to maintain its TDP. With a non boost bios it seems you can maintain the high clocks with less voltage and no throttling but this requires flashing the bios. I imagine the stock boost bios volts high so all cards will achieve some kind of higher boost clock even the lemon chips.

AMD can claim performance better than the 670 when under boost but the cards just do not cope with it very well and reading on the web the throttling issue seems to be an issue on both the 7950 & 7970 cards.

That's my theory on this one.
 
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It is a pain as I'm sure a bios flash if possible would fix the problem but I'm not willing to risk flashing the bios and possibly bricking a two day old card. It has a dual switch but with reports of not being able to flash who knows if it actually has a dual bios.

AMD have really mucked up what was a decent card with the boost bios. The performance is horrendous in game with spikes and jumps all over the place. It's so obvious the only reason the boost bios is there is to get the numbers up for sales purposes.
 
LtMatt said:
I think you'll find HIS mucked up. AMD are not responsible for a faulty bios created by an AIB.
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AMD designed the boost bios and set the voltages from what I have read. There are quite a few other cards inc 7970's having issues with boost type bios's.

My reference 7970 runs a constant 1200 on the core. I might try a boost bios on it and see if it fluctuates.
 
LtMatt said:
I've had a good look round but cannot see a lot of other cards having this issue. Where are you getting this from?
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I do not wan't to link to other forums but if you search there a quite a few brands with the same problem using the boost bios.

A few examples from a quick search.

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 (%).
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The boost bios acts like that it's a well documented problem that AMD are choosing to ignore.
7950BClockspeed.png


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 a lot 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).
Click to expand...

My Windforce 7970 cannot maintain it's 1100Mhz clock it drops off suddenly causing jumping in Battlefield 3 ?
Click to expand...
 
Chrisoldinho said:
you are a star. i have looked everywhere for this :D

last question, is the 7950 iceq boost a reference design?
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From what I read it is based on a reference design but uses cheaper Elpida ram instead of the Hynix of the reference. This can cause some stability issues when flashing bios's.

Let us know how you get on as I'm interested to see if it works.
 
LtMatt said:
Moogleys have you increased the power slider to +20%? As i can replicate a similar issue on my card when i exceed my cards TDP limit.
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Yes mate no difference. Tbh I kind of get the feeling no matter what I do voltage wise the card overrides it and does it's own thing. Under volting the card only seems to apply to the stock speed as soon as the card boosts it whacks 1.25v up its pipe which I think is why it is hitting it's TDP and dropping the clocks to compensate.
 
No idea but it's something on the card as all my other GPU's run ok. I think it could be fixed with a bios flash if there is one that works but I'm not willing to try that and void the warranty.

I would rather send it back under the returns and get something without a boost bios if there is anything now.

I have saved the His bios from the card and I'm going to try and flash it to my 7970. I have no idea if this will work orif it is even possible tbh.
 
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I think I have fixed it. This is my usage now no more jumping around and a nice constant core speed. Will give it a good testing and see how it goes before getting to excited. :)

Untitled-36_zps2e37e06a.jpg
 
All I have done is installed the latest beta of afterburner and forced a constant voltage. So far for some reason it is not boosting and just staying constant.
 
I tried this before and nothing happend. It seems to work with the beta afterburner. Strangely the voltage and clocks are dropping when in idle.
 
I will give it a good testing later and make sure all is OK. Just seems a bit weird that it is not boosting and even with a forced voltage it is still dropping down at idle.
 
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