7850 Crossfire has failed me this round. Sent 2nd card back. Sticking with one card.

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jacktesterson

Diamond Member
Sep 28, 2001
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Is this with virtu or without virtu? How high is the oc? A stock 7950 prolly scores less than this


Rig in system

2500k @ 4.7

No Virtu (As far as I'm aware, never set anything regarding this, never really looked into it)

Single 7850 @ 1200/1400

8GB DDR3 1866
 
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jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
You're getting close to stock 7950 performance. How much room is left?

I haven't gone any further. I discovered that no matter what software I use, I can't get the GPU past 1.165v. This is what I'm using at 1200/1400 and haven't had any issues. at 1225 I get freezes.

Ive got GPU tools that will set past 1.165v, but according to different monitoring tools, it never goes past 1.165v under load no matter what I set.

Any ideas what the issue is?
 
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aaksheytalwar

Diamond Member
Feb 17, 2012
3,389
0
76
Many 7970's can do 40%. :) But two 7850's would obviously be better bang for the buck (assuming the gamer using that set up is ok with multi-card setups).

If you can live with the noise or apply arctic cooling, yes half of 7970s would do about 40% oc on air. However I would rather settle for 1150-1200 for more life etc. and I would prefer a single 7970 40% oc to 7850 40% oc cf due to no ms, more smoothness, no hassles etc

Btw, my 1000th post :)
 

SlowSpyder

Lifer
Jan 12, 2005
17,305
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If you can live with the noise or apply arctic cooling, yes half of 7970s would do about 40% oc on air. However I would rather settle for 1150-1200 for more life etc. and I would prefer a single 7970 40% oc to 7850 40% oc cf due to no ms, more smoothness, no hassles etc

Btw, my 1000th post :)


I'm not disagreeing with you at all. He said that they'll never see 40%, I was just pointing out that 40% is in fact doable. My 7970 will go over 1200MHz, no problem, but I can't live with the noise. Somewhere around 1125-1150 is about where I like to keep it clocked, it doesn't make too much noise around those speeds. But above 1200MHz, it's like a vacuum cleaner. :/
 

jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Well my 7850 got delayed in transit for some reason. Looking more like Wednesday now. Damn free shipping slowness.

Always something.

On a side note, I decided to tune back my 2500k from 4.7 to 4.4 and my 7850 from 1200/1450 to 1180/1350.

The difference in performance is less than 5%, with my voltages being WAY lower so less heat.

(I was running 1.41v @ 4.7 GHz, but can do 1.30v @ 4.4Ghz, saving a good 10 degrees max temps)

It required a full .11v increase for only 300 MHz difference, so its not worth it right now.
 
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jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Well folks,

I had a lot of trouble getting my Asus 7850's to work in Crossfire, as the rumors are true. The drivers are a mess....I mean can't even browse the internet without rebooting (pc @ 100% stock) for more than 5 minutes mess. 12.3, 12.4 and 12.5 beta all would not work as soon as Crossfire was enabled. Each card on there own, in either PCIe slot, would work 100%.

Anyways, turns out the oldest drivers that support the 7850 (12.2 Betas?) are the only ones that won't make my computer puke.

So here we are. I have limited time over the next 5-6 days, but thought I'd share a 3DMARK11 score.

System in Sig (2500k @ 4.6Ghz, 8GB DDR3 1866, 2 x 2GB Asus 7850 1175 Core/1400 Memory. First O/C Done to cards that passed limited occt stability)


3dMARK11 - P11543

http://3dmark.com/3dm11/3390827;jsessionid=1amx7ce5aycvjte4tafw26a80
 

Don Karnage

Platinum Member
Oct 11, 2011
2,865
0
0
Well folks,

I had a lot of trouble getting my Asus 7850's to work in Crossfire, as the rumors are true. The drivers are a mess....I mean can't even browse the internet without rebooting (pc @ 100% stock) for more than 5 minutes mess. 12.3, 12.4 and 12.5 beta all would not work as soon as Crossfire was enabled. Each card on there own, in either PCIe slot, would work 100%.

Anyways, turns out the oldest drivers that support the 7850 (12.2 Betas?) are the only ones that won't make my computer puke.

So here we are. I have limited time over the next 5-6 days, but thought I'd share a 3DMARK11 score.

System in Sig (2500k @ 4.6Ghz, 8GB DDR3 1866, 2 x 2GB Asus 7850 1175 Core/1400 Memory.


3dMARK11 - P11543

http://3dmark.com/3dm11/3390827;jsessionid=1amx7ce5aycvjte4tafw26a80

Looking a lot better then last night. 1200 core? :)
 

jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Single Card Graphics Score- 6880

Crossfire Graphic Score- 13150

91% Scaling on Graphics score.


Don, I got the better results after installing the 12.4 Caps

Got a Question for you or anyone else, I've discovered when I go higher than 1175, I am getting throttling and my Performance actually is much worse. I never noticed this when 1 card was running. Any ideas how to get around this? Higher Fan speeds when benching?
 
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Don Karnage

Platinum Member
Oct 11, 2011
2,865
0
0
Single Card Graphics Score- 6880

Crossfire Graphic Score- 13150

91% Scaling on Graphics score.


Don, I got the better results after installing the 12.4 Caps

Got a Question for you or anyone else, I've discovered when I go higher than 1175, I am getting throttling and my Performance actually is much worse. I never noticed this when 1 card was running. Any ideas how to get around this? Higher Fan speeds when benching?

What do you have your "Powertune" setting at?
 

jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Is that the power slider in the CCC? Its at 20%. If not, please explain.

It looks like my 2nd card is a Dud. I'm needing to use more Voltage than I want just to get the 2nd card stable at 1200.

1st card at 1200 - 1.170v
2nd card at 1200 - 1.225v


I still think I'm throttling, as I can complete 3DMARK11 at 1225 @ 1.24v , but my score is a little worse than 1175 core.
 

Don Karnage

Platinum Member
Oct 11, 2011
2,865
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0
Is that the power slider in the CCC? Its at 20%. If not, please explain.

It looks like my 2nd card is a Dud. I'm needing to use more Voltage than I want just to get the 2nd card stable at 1200.

1st card at 1200 - 1.170v
2nd card at 1200 - 1.225v


I still think I'm throttling, as I can complete 3DMARK11 at 1225 @ 1.24v , but my score is a little worse than 1175 core.

Probably throttling bro. Amd limits on these cards are super low
 

jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Probably throttling bro. Amd limits on these cards are super low

Going to do some reading into this today when I get a chance.

I've only benched 3DMARK11 so far, but 1175/1375 is giving me the best result. As soon as I try 1200 or higher, my score drop in the 10k's. It starts fine then drops within seconds of the bench starting, indicating to me my cards are throttling, even with 20% set in Powertune.

Question - In Overdrive, it only allows me to set the Powertune setting on 1 card only.... (when I choose 2nd card, the slider is there, but it won't let me save my setting). Is this normal? Is the first card setting being applied to both?
 

jacktesterson

Diamond Member
Sep 28, 2001
5,493
3
81
Get Sapphire TRIXX, it can set TDP (powertune) limits to +50%!


Will give Trixx a try tonight, although honestly, I'm quite happy with 1175/1375 crossfire performance right now, plus my temps are quite low, so I'll probably leave it here for a year or so. Will still play around to see how high I can push them though if A) Figure Throttling Issue (Hopefully Trixx) and B) AMD Actually releases WHQL drivers that work with 7800 series in Crossfire.

GPU 1- 1175/1375 @ 1.155v

GPU 2- 1175/1375 @ 1.190v

As you can see, my newer Asus card is not nearly as good as my first one for overclocking.
 

aaksheytalwar

Diamond Member
Feb 17, 2012
3,389
0
76
Honestly, this isn't much faster than a single 7970 OC. My 7970 OC scores nearly 10k in P10k ish or so, just 200-300 points or so lower I guess :)

And CF anyways feels like 2/3rd the FPS in terms of smoothness and experience, so sub 12k will actually give a worse experience with CF hassles, MS, less smoothness, more heat etc, at the price of a single 7970 :D