HD 5750 OC

[Roark]

So I'm OC'ing my 5750 through MSI afterburner and had a few questions.

1) Is there a certain ratio I should aim for between Core and Memory Clocks?
Currently at 850/1300 and it seems to be running fine, push more on the Mem or does it matter.

2) How reliable is MSI Kombustor's temp gauge?
It was reading 85°c, while HWMonitor read a max of 74°c.

3) Any reason CPU-Z Graphics tab is reading Mem at 1300 but Core at 399?
Even if it was reading stock it should be 700/1150.


*Edit

Just pushed speeds as high as I could get it stable, seems to be fine at 850/1400.
Tried 855/1425 and that crashed FurMark, which I switched to instead of Kombustor.

Still not sure why CPU-Z isn't displaying the proper Core speed though.

[Sean W.]

just like regular memory, GDDR5 memory on graphics cards dont really yeild any kind of performance gain from being overclocked, bring the memory clock down a bit and see how high you can ramp the GPU. you dont want an unstable memory overclock to affect your processor overclock!

[Roark]

Tested at 1680x1050 + MSAA 2x, Fullscreen, Dynamic Background.
10min burn-in so temps would plateau, 5min cool down, started at 49°c.

Core/Memory - FPS min/max/avg (temps were consistently 85°c max):
850/1400 - 13/16/13
855/1350 - 12/16/12
860/1350 - 12/16/12
865/1350 - 12/16/12
865/1375 - 12/16/12
870/1375 - 12/16/12 (Core slider maxed @870)
870/1400 - 13/16/13 (Stopped here since 1425 crashed it before)

[Sean W.]

^ those are the most bazaar overclocking results ive ever seen...

im not really sure what to make of that.

i would say bench with an actual game/bench program. like the heaven benchmark. not to mention a real benchmark program might even show you how stable ( or not ) your OC really is...

[Roark]

Ran Unigine Heaven benchmark with a sample of above
DX11 1680x1050 Fullscreen, 2x AA, 4x Anisotropy

Core/Memory - FPS min/max/final - Score
(Didn't reset HWMon, overall max 70°c)

850/1400 - 9.4/44.2/20.9 - 527
860/1350 - 10.5/44.6/21.1 - 532
865/1375 - 10.3/44.7/21.3 - 535
870/1400 - 10.6/44.8/21.2 - 533
870/1375 - 10.6/44.9/21.2 - 533
870/1350 - Crashed Drivers

[Sean W.]

looks to me like 865/1375 is the sweet spot. ramp the voltage as low as it will let you go, while remaining stable to keep the temps and noise down and cruise from there

[Roark]

Afterburner won't let me unlock Voltage Control/Monitoring.
Went in to settings and check the boxes, but no go.

Is it just me or is it a little weird that I got higher min/max at 870 Core, but lower final and score?

[Sean W.]

im thinking its your CPU bottle necking the performance...

[Roark]

Pumped the E8400 back up to 3.6GHz from 3.0GHz. Was leaving it at stock since it was hitting 84°c running P95 before.
New (top mounted) PSU with a 120mm drawing heat off the CPU seems to be keeping temps down though.
Currently running P95 again, maxing at 62°c so far.

CPU @ 3.6GHz (Overall max CPU temp 56°c)
865/1375 - 11.4/44.9/21.3 - 535
870/1400 - 6.5/44.9/21.1 - 531
870/1375 - Crashed Drivers

looks to me like 865/1375 is the sweet spot.

The data don't lie, +rep.