Can't OC HD 7950

NoWorthWhile

Junior Member
Feb 26, 2012
16
0
0
Hi,

I've got a 6 weeks old Powercolor PCS+ 7950 HD Radeon, and have a couple of issues with it. Although the card is whisper quiet up to 40% fan speed, I can't overclock it past 950 MHz core...

I've tried first with AMD Overdrive, and got it up to 950 MHz. I was pleased with it (BF3 was going from 48 up to 60 fps with vsync on, on 1200p) but was looking to go a little further as I'm looking to buy a 1440p monitor soon. So I tried sliding the "Power Control Settings" to +20%, and set the core to 1000 MHz, Memory to 1575 Mhz. BF3 ran with glitches.

I then used MSI Afterburner to try to up the voltage up to 1.09 V, and the game crashes the computer (freezes, monitor disconnects/reconnects, only a hard reset fixes it).

Am I missing something?

Also, inside of AMD CCC, I updated twice to 12.4, but I'm still on 12.3... Go figure.
 

aaksheytalwar

Diamond Member
Feb 17, 2012
3,389
0
76
Temperature?

And your volts are too low for a proper oc at least for a 7970. You will need to go closer to 1.2 for a max oc
 

NoWorthWhile

Junior Member
Feb 26, 2012
16
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0
I value silence a lot in this build, that's why I went with this model and made a custom fan profile to keep the noise in check. It goes up to 40% at 70C. I just played a round of BF3 at 950Mhz Core, and temp stayed between 60 and 65C.

I'm in the process of uninstalling all drivers + MSI Afterburner, and will install 12.4 + Trixx, and will report back.

Thanks for the help.
 

Don Karnage

Platinum Member
Oct 11, 2011
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I value silence a lot in this build, that's why I went with this model and made a custom fan profile to keep the noise in check. It goes up to 40% at 70C. I just played a round of BF3 at 950Mhz Core, and temp stayed between 60 and 65C.

I'm in the process of uninstalling all drivers + MSI Afterburner, and will install 12.4 + Trixx, and will report back.

Thanks for the help.

Install 12.5 beta's

http://www.techpowerup.com/164961/AMD-Catalyst-12.5-Beta-Leaked.html
 

blackened23

Diamond Member
Jul 26, 2011
8,548
2
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You could install an accelero to improve your OC and be whisper quiet even at 100% manual fan. I got a 7970 to 1300 stable during stress testing using one of those things, they are amazing. They are too freakin expensive though, i'd try to get one used if anything.
 

Don Karnage

Platinum Member
Oct 11, 2011
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You could install an accelero to improve your OC and be whisper quiet even at 100% manual fan. I got a 7970 to 1300 using one of those things, they are amazing. They are too freakin expensive though, i'd try to get one used if anything.

How well did it perform at 1300?
 

blackened23

Diamond Member
Jul 26, 2011
8,548
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I value silence a lot in this build, that's why I went with this model and made a custom fan profile to keep the noise in check. It goes up to 40% at 70C. I just played a round of BF3 at 950Mhz Core, and temp stayed between 60 and 65C.

I'm in the process of uninstalling all drivers + MSI Afterburner, and will install 12.4 + Trixx, and will report back.

Thanks for the help.

Why bother with drivers? Personally, i'd suggest not using the 12.5 betas, but just use MSI afterburner 2.2.1....it was just released a couple of days ago. Try to see how you feel about 50% manual fan, you might have a bit more room for OC'ing there.
 

blackened23

Diamond Member
Jul 26, 2011
8,548
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Errrr, dafuq? Just installed 12.4 from AMD's website, and CCC still says it's 12.3 ...

Don't worry about it. You probably did an overlapped driver install or something. If your driver packaging version is this (per CCC) 8.961-120405a-137224C-ATI you are indeed using 12.4.
 

Stuka87

Diamond Member
Dec 10, 2010
6,240
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Something is not right here. The temps you shows are WAY high for that card at that speed. You should only be at around 50-55 at full load at 950. I am wondering if your heatsink has too much thermal compound, not enough, or is just a more mating surface.

Also, drop your memory back to default. There is no reason to OC the memory if you are under 1100Mhz core. Your memory may be causing your issues. Especially since you are not crashing, you are just seeing artifacts.
 

NoWorthWhile

Junior Member
Feb 26, 2012
16
0
0
Alright, currently in BF3, with Trixx

Here are the settings:

1050 Mhz Core
1250 Mhz Mem
Board power 20
Vcore 1100 mV

sitting at 61C @ 45%.

What now? Dial down the Vcore? Go up with the core frequency?
 

Stuka87

Diamond Member
Dec 10, 2010
6,240
2,559
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Alright, currently in BF3, with Trixx

Here are the settings:

1050 Mhz Core
1250 Mhz Mem
Board power 20
Vcore 1100 mV

sitting at 61C @ 45%.

What now? Dial down the Vcore? Go up with the core frequency?

Is it stable at these settings? Or are you still getting corruption? This is probably the max speed you will get without voltage tweaks.
 

Don Karnage

Platinum Member
Oct 11, 2011
2,865
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Alright, currently in BF3, with Trixx

Here are the settings:

1050 Mhz Core
1250 Mhz Mem
Board power 20
Vcore 1100 mV

sitting at 61C @ 45%.

What now? Dial down the Vcore? Go up with the core frequency?

Temps are fine. Keep going up with the core.
 

NoWorthWhile

Junior Member
Feb 26, 2012
16
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Yes, it is stable. But it isn't standard voltage, is it?

@Don, okay, will do. Trying some raiding in WoW right now, to see the effects. Not as intensive as BF3, but at least it represents a real test scenario.
 

Don Karnage

Platinum Member
Oct 11, 2011
2,865
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Yes, it is stable. But it isn't standard voltage, is it?

@Don, okay, will do. Trying some raiding in WoW right now, to see the effects. Not as intensive as BF3, but at least it represents a real test scenario.

Your voltage is super low. Safe voltage is up to around 1225mv but can take up to 1300mv so as long as temps are under 90C continue.
 

blastingcap

Diamond Member
Sep 16, 2010
6,654
5
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http://www.guru3d.com/article/powercolor-radeon-hd-7950-pcs-review/

They could barely break 1000MHz without overvolting, and they did NOT underspeed the fans, so if you insist on underspeeding, you may get worse results.

Furthermore, not all 7950s are made from perfectly-functional 7970s with some shaders laser cut off. Some 7970s had defects and couldn't hit 925MHz as easily as they should have, so they got down-binned to 7950 status. You can't expect those semi-defective chips to clock as highly as 7970s can, on average.
 

Stuka87

Diamond Member
Dec 10, 2010
6,240
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Yes, it is stable. But it isn't standard voltage, is it?

@Don, okay, will do. Trying some raiding in WoW right now, to see the effects. Not as intensive as BF3, but at least it represents a real test scenario.

1.1V is stock (well, some are like 1.095 or so, mine was).

Now if you end up over voltaing and go up to 1200 or so core, then you can experiment with raising the memory speed. But realistically you only see a gain is specific cases, so I would not consider it a priority to raise the memory speed up.
 

Don Karnage

Platinum Member
Oct 11, 2011
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http://www.guru3d.com/article/powercolor-radeon-hd-7950-pcs-review/

They could barely break 1000MHz without overvolting, and they did NOT underspeed the fans, so if you insist on underspeeding, you may get worse results.

Furthermore, not all 7950s are made from perfectly-functional 7970s with some shaders laser cut off. Some 7970s had defects and couldn't hit 925MHz as easily as they should have, so they got down-binned to 7950 status. You can't expect those semi-defective chips to clock as highly as 7970s can, on average.

Thank you for sealing the deal on me never buying a 7950
 

NoWorthWhile

Junior Member
Feb 26, 2012
16
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0
OKay, seems reasonably stable and cool at around 60C @<40% fan speed under WoW.

I'm trying now 1100 Mhz Core under BF3.

(Under BF3, I'm not so concerned about noise, as I'm using a headset, but under WoW, I want it under 40% fan so it can be whisper quiet.)