How to overclock a 7850 past 1050MHz?

.:SAmSuNG:. · 1 Jun 2012 at 19:11

Been clocking abit and so far this is best ive had.

Core 1200Mhz
Mem 1375Mhz
Voltage 1.25v
Board Power +20%.
12.6 Beta Drivers.
i5-2500K @ stock
8GB DDR3 1333mhz

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[Damien];22043793 said:
At max catalyst settings w/ stock voltage my card runs and passes heaven fine, If I so much as bump the core up to 1100 from 1050 heaven causes the gfx driver to crash and restart. Bumping the voltage up to 1100 or even 1225 has no effect on stopping it crashing. I've tried with both the memory @ stock speeds, or at max catalyst settings (5800).

Baby steps are needed I think...

snip

I wondered why your results were so high but then you dont have tessellation enabled.

Balb0wa · 1 Jun 2012 at 19:31

Upped the memory a bit on mine

MSI HD 7850 Power Edition Twin Frozr IV OC
Core 1250Mhz
Mem 1400Mhz
Voltage 1.25v
Board Power +00%.
12.6 Beta Drivers.
i5-2500K @ 4.5 Ghz
16GB DDR3 1600mhz
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.:SAmSuNG:. · 1 Jun 2012 at 19:33

what voltage you need for that?

Balb0wa · 1 Jun 2012 at 19:33

.:SAmSuNG:. said:
what voltage you need for that?

1.25

.:SAmSuNG:. · 1 Jun 2012 at 19:51

What card you have? Mines locked to 1.225v max.

Balb0wa · 1 Jun 2012 at 19:55

.:SAmSuNG:. said:
What card you have? Mines locked to 1.225v max.

MSI HD 7850 Power Edition Twin Frozr IV OC

Arron17 · 1 Jun 2012 at 20:24

Mine only goes upto 1.225v too, its a shame because I know I would get at least 1250 with 1.25v.

Although My scores are a tiny bit higher than Balb0wa's. I'm talking 0.5fps.

.:SAmSuNG:. · 1 Jun 2012 at 21:12

Yea i dunno if its really worth it. Im happy with 1200mhz core. Just want to try lower voltage alittle and find the memory sweet spot.

Arron17 · 1 Jun 2012 at 21:37

.:SAmSuNG:. said:
Yea i dunno if its really worth it. Im happy with 1200mhz core. Just want to try lower voltage alittle and find the memory sweet spot.

Well I've managed 1200 on 1.185v and I think someone else on here got it on 1.170v, max memory I can have is 1475mhz

.:SAmSuNG:. · 1 Jun 2012 at 21:44

Do you find that memory speed gives best fps?

Arron17 · 1 Jun 2012 at 22:01

.:SAmSuNG:. said:
Do you find that memory speed gives best fps?

It seems to on my card, might be different on yours. I'm just about to do a couple of benches to test it actually. Because I haven't really tested that out. I know I get grey screens at 1500mhz. I'll report back in a few minutes.

.:SAmSuNG:. · 1 Jun 2012 at 22:07

Managed to get 1250Mhz/1400Mhz to run heaven but wont go any higher on core without flashing the bios to allow more voltage.

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liamcrane · 1 Jun 2012 at 22:20

What is the max voltage you can put through an MSI 7850?

.:SAmSuNG:. · 1 Jun 2012 at 22:21

1.3v i think but dont think its recommended for 24/7

Arron17 · 1 Jun 2012 at 23:26

.:SAmSuNG:. said:
Do you find that memory speed gives best fps?

These are what I managed to get, everything on full for all the benches with vsync off running 1200mhz core.

Crysis 2

MEM FPS1 FPS2 FPS3
1550 55.83 54.17 Crash
1525 55.83 54.05 54.02
1500 55.36 53.41 53.51
1475 55.28 53.62 53.66
1450 54.95 53.49 53.44
1425 54.45 52.86 52.77

BatmanAC

MEM FPS1 FPS2 FPS3
1475 74 74 74
1450 73 74 74
1425 72 73 73

Just Cause 2
MEM FPS1 FPS2 FPS3
1475 61.06 60.42 60.24
1450 59.85 59.73 59.96

battleponcho · 2 Jun 2012 at 00:15

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First run is stock 920/1150, Sapphire OC edition
Second is 1100/1500 @ 1.75v
Should shed some light on the Core clock vs memory clock fps question.

With the volt that low in the safe zone I think i'll call it a day. My card isn't very core clock friendly but memory clock it seems to be okay with to pump up.

Twirlywoos · 2 Jun 2012 at 00:31

.:SAmSuNG:. said:
What card you have? Mines locked to 1.225v max.

What utility are you using? Try using Sapphire Trixx and you can reduce the Voltage with that.

.:SAmSuNG:. · 2 Jun 2012 at 00:36

majnu said:
What utility are you using? Try using Sapphire Trixx and you can reduce the Voltage with that.

Sorry i meant thats the max it allows. I want to raise it higher but I dont think its possible without a bios flash.

Also it looks like 25Mhz in memory is close to 1fps gain.

degenerator · 2 Jun 2012 at 00:37

Lets say I put fan speed at 100% (lets say sound isn't an issue) what would the max I could overclock it to, whilst remaining stable?

Twirlywoos · 2 Jun 2012 at 00:37

battleponcho said:
First run is stock 920/1150, Sapphire OC edition
Second is 1100/1500 @ 1.75v
Should shed some light on the Core clock vs memory clock fps question.

With the volt that low in the safe zone I think i'll call it a day. My card isn't very core clock friendly but memory clock it seems to be okay with to pump up.

First of all Tesselation should be normal; Anisotropy should be 4X and you should run 4X Anti Aliasing.

It's the Core speed that needs to be notched up. Once you crash in heaven; up the Voltage but don't exceed the recommended threshold or whatever you consider to be a safe temperature. Also it's worth noting that people have their GPU's liquid cooled so if they get higher benchmarks, it's because they can push their cards higher than those on air coolers.

Additionally, there will come a point where the over voltage protection will kick in, so whilst you can push higher clock speeds the Heaven score will start to decrease.

The process of overclocking is an iterative process, where you gradually make changes and test to see how stable it is. You should only be making one change at a time so that you can assess if the change improves things, if it doesn't change it back and change something else. Also keep a note of your last stable settings so that you can revert to them if you reach a point where several minor increases in voltage etc makes no difference to stability.

TL;DR This is an example of how I approached overclocking.