Max OC stable 5850 Xtreme?

[khrystiano]

Hi, I got this card and I just wanted to know if the performance will be increased if I do some overclock to the card, my card is working at 725/1000, what do you guys think is the max. oc stable without touching any voltage? I'ts worth to oc the Memory Clock?

greetings!

 

[khrystiano]

bump!

 

[KingFatty]

Yes, overclock of the core will increase performance. If you don't bump the voltage, maybe you can experiment with how high the core will go. Maybe 800, or 850? During that experiment of raising the core speed and testing, leave the memory speed alone.

For the memory, you could try overclocking, but it's very tricky because you can get slower performance with higher speeds. The reason is the 5850 has good error correction for the memory. So, when you start getting errors, you won't see them because of error correction, but the performance is worse because error correction is being applied. So, you want to find a sweet spot where you raise the memory speed enough to get slightly better performance, but not enough to get errors. This can involve lots of exhaustive testing.

So find your comfortable core speed first, then go after the memory separately.

 

[khrystiano]

So u basically recommend me to raise the core but let memory by default speed? I used to play with 850/1200 and all seems ok but I recently tried 885/1225 and it crashed...

I tried The Witcher 2 with 725/1000 and then with 850/1200 and seems like I get some extra fps with the OC, maybe 1200 is the limit?

 

[KingFatty]

Change one thing at a time, or else you will never know which is causing the problem if you change both the core speed and the memory speed.

Find out how fast your core can go, leaving the memory at stock speeds. Then find out how fast your memory can go, leaving the core at stock speeds. As mentioned above, finding out the max memory speed is tricky because a lower number could end up being faster, due to error correction memory, so you really have to benchmark the card at different speeds to see the results.

Another thing that might blow your mind is that you may even get best results by *reducing* the memory speed, if that means your core can be overclocked even more than if you leave the memory speed stock.

Best case is you run a benchmark and test test test. Make a spreadsheet, and track your results for different combinations of core and memory speeds.

 

[khrystiano]

Oh, I see, so I should oc the core with the memory in stock and see how far can go, then, I'd reset the core to stock and try to OC the memories and try some benchmarks...

3DMarks can work for that?

 

[SPBHM]

try using unigine heaven or something, 3dmark free is to limited,

but basically yes, test the core or memory OC until it's unstable and then go back a bit (test separately and then both at the same time)

850/1200 is good for stock voltages, my reference 5850 (1.088v) can only do around 840/1100 (with overvolt it can go well over 900 on the core, but memory is stuck at 1100)

but keep in mind, even if it runs unigine heaven or 3dmark fine with the OC, it could still be unstable in a game, so... test with your favorite games

 

[khrystiano]

Hi and sorry for my late answer. I've been trying different core/memory speeds and thats what I've found:

If I raise the core the benchmark crashes, the same with the memory... so, what do you guys think? shoud I enable or use another filters in Heaven's bench?

Also, with 855/500 the max temp reached was 58º, with 855/1075 the max temp reached was 65º, is that ok? Can I raise the voltage safely without gettin high temps?

Im curious because in some games (like League of Legends) the grpahic card doesnt reach the 99% of use, indeed it stucks at 25/30%, when I start the game I get like 300fps but it wont last at all, it decreases during the game and the core/memory sometimes goes to 550/900 instead 855/1075 / 725/1000, is that normal?

 

[Headfoot]

65 is 100% fine. You shouldn't let it go over about 80-85c, anything below that is fine.

 

[khrystiano]

Thanks, and what 'bout raising the voltage? it'd be safe? how much will increase the temp if I raise it to allow the 940/1200?

 

[Headfoot]

Thanks, and what 'bout raising the voltage? it'd be safe? how much will increase the temp if I raise it to allow the 940/1200?

You tell me. The only way to find out is to try. Google 5850 max voltage to find out what people regard as the safe top-end volts.

 

[khrystiano]

Thanks but I've tried to raise the voltage with MSI Afterburner but it dont let me do it... Is there another way to touch the voltage without the trixx program?

 

[Headfoot]

There's a voltage unlock button in MSI Afterburner. You might have to go into a text file and change EULA=true. I can't recall the specifics, try googling "msi afterburner unlock voltage 5850" and see what comes up. I had to do that on my buddies 5850 back in 2010.

 

[SPBHM]

as far as I can remember there is a clear option to enable voltage control (but default is off), and no .ini change is required,

as for max voltage...

the highest voltage a reference card with this GPU used was 1.18v as far as I know (older reference 5870), so I always considered that to be "safe" (if you can cool it enough), but people went over 1.2v back in the day for 1GHz and such OCs, it seems like under 1.12v is pretty OK with my 5850 and the 2009 reference cooler (with a custom fan profile, still under 40%),

not sure if the VRMs are as good/well cooled on the "Xtreme" as the reference card,

 

[khrystiano]

Okay, thanks!

So i tried TRIXX and 1180 volt. 900/1100 and no errors but the temp stucks in 73º-74º with the fanspeed to 88%... is that worth? is there any risk tu puttin the card so high?

greetings

 

[khrystiano]

bump!

 

[Headfoot]

73-74 is just fine, good even. The real question is whether the 88% fan speed is too loud for you or not. If its not loud or you dont mind the noise I'd say it's probably worth it.

 

[khrystiano]

So I'll assume it's totaly safe even with that fan speed at 88? I thought I could break the fan at that speed...

So, do you think I can reach 940/1250 with 1180 volt. or shoud I raise it?

Greetings for all!

 

[Headfoot]

Yeah fan isnt going to break if you turn it up. I can't tell you what voltages will work. The only way to find out is to do it. Every chip is different, I can't tell you how yours is going to perform man. Generally speaking you want to have the lowest volts possible for a given clock speed. You'll have to raise volts to raise clocks. There is a max safe voltage, probably around ~1.2v reading SPBHM's post above.

 

[khrystiano]

Okay now I see... thanks!

One more question.

What's the safest temp for the daily use and to play games diary?

I have 37º on idle with the fan stuck on 65%

Thanks for all guys!

 

[Headfoot]

For those older 5850's I'd say try to keep it under 80 C for the most part. If every once and a while it goes a little above that, it would still be fine, but I wouldnt run it 24/7 at 85+ IMO.