Asus HD 5850 overclocking advice please

[mark_j]

Crysis and Warhead are my favorite games (I've played through each several times and also play various mods, custom maps, etc.) I game at 1920x1080 and really enjoy playing with max in-game settings and 4xAA. Overclocking my video card makes this possible, but I have been disappointed so far with my results.

My system:
i5-750 21x160 1.17v 12hr Prime stable
4gb Corsair DDR3
WD 750gb SATA HDD
MSI P55-GD55
Asus HD5850
Corsair 750w power supply
Cooler Master CM690 case
Windows 7 HP 64-bit

I have achieved the following unimpressive results with MSI Afterburner and the Crysis Benchmarking Tool:
775/1125 1.088v: 30-31 fps, but dips into the low 20's make this unacceptable
825/1125 1.149v: 32-33 fps, much better but need just a little more fps to stay smooth all the time (big explosions, etc)
850/1200 1.164v: 35-36 fps, this is smooth all the time but I sometimes get white-dot artifacts

I use the custom fan profiler in Afterburner to keep my temps under 65c. Anything less than the voltages shown above at the given speeds results in a benchmark freeze and a hard reboot. After reading various "stock voltage huge overclock" success stories I am a little frustrated with my results.

I want 850/1200 with no artifacts but do not know how to make that happen. Any advice would be appreciated.

Thanks
Mark

 

[MarcVenice]

Fuck mem speed. It doesn't do anything for framerates. So clock it back to 1150MHz and see what happens. Still got white dots? More voltage! If you don't want to give the gpu more volts, clock it back 5MHz each time. I hardly doubt 25MHz makes a noticable difference btw.

 

[mark_j]

More voltage will help the white dot problem? Ok, thanks, I'll try that.

edit: Also, upping the memory from 1125 to 1200 does give an exta 1-2 fps, which is something when you are running near 30 fps avg. I was extra careful to check the gain resulting from memory OC after reading about the possible performance hit caused by error correction.

 

[TJ Tom]

Start with upping the core and do benchmarks and stability tests while you're at it. I use Furmark for the "stability" testing although it's not recommended I find it a good and easy to use tool to spot artifacts or dots or whatever might pop-up while overclocking your video card.

Memory overclocking does provide a performance boost but it's so minimal it often aint worth it to overclock it to 1200+, anyway, those are my findings.

This is what I do, I up the core and bench, test, up the core again and bench/test and so on. When I have a nice OC on my core I check how high I can up the memory without it holding back my core clock. I'm not a pro in overclocking but I've found that OCing memory can result in lesser performance when my core is at 850 Mhz or higher.

My personal core voltage limit is 1.3v but I often try to stay below my "limits". The lower it is the longer I can enjoy the card imo.

I also have a HD5850 currently at stock since I'm waiting for Fermi to prove it won't beat the HD5850 in price/performance (not trying to start a fanboy flamewar ) just so I can buy a second card and put some waterblocks on it so I can take it way higher.

 

[Tempered81]

More volts on the core, keep it cool. I wouldnt worry about mem over 1200 either... After 1200 it's a crap shoot.

Core might go to 1050ish on ~1.3v Looks like you're gonna need ~1.25 for 975+ mhz

Which drivers are you using?

 

[PUN]

You need more juice to the core if you are getting artifacts.
Usually a video memory failure would just give you a blank screen or reset your computer.

 

[bradyapba]

what are your mem temps?

 

[mark_j]

Ok...I fed the core 1.18v and the white dot artifacts disappeared. I tried pushing the core to 875 and it crashed, so I backed it down to 850 (which is what I was shooting for anyway).

Thanks everyone for their advice. I thought no crash + artifacts meant I had too much heat, I never would have though more voltage would be the fix.

Edit: someone asked what drivers I'm using (10.2)