5970 Overclocking Questions

masterkaj

Junior Member
Dec 22, 2007
24
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Been in the market for a video card for the past few months, finally got a good deal (after bing cashback) on a Sapphire 5970 (600 shipped). Figured it's about the same price as 5850 crossfire, so why not.

Anyways, once I installed it I ran some stock benchmarks(1.049v/725/1000) in heaven 2.0. The settings I used were 1680x1050, normal tesselation, 4xAA, and 16xAF. After a few runs the minimum FPS average was around 20.5.

Next I used Furmark and Vantage to test the stability of overclocking, finally got it stable at 1.100v/850/1200. However, when i ran the Heaven 2.0 benchmark; the beginning of a dark scene (stage 20 or so) would cause the min. fps to drop to 8(only in this scene). The avg FPS was around 14% higher than the stock run, but the minimum fps was horrid. I ran the test multiple times, always the same result.

I then upped the voltage to 1.125 and the problem went away, minimum fps around 22. So my question is, what exactly is the best way to test and make sure my core voltage is high enough. I know about the standard artifacting/freezing up, just never heard of the minimum fps issue. Right now I am using Furmark, 3dmark Vantage, Heaven 2.0, and BFBC2 to test it out.

I know a lot of people with the 5970 just up the core to 1.167 and don't worry about it, but I figure the lowest stable voltage would be best.

I ran BFBC2 last night for 4 hours and the core and vdcc temps stayed around 82*C, this is on the stock auto fan profile too(2500 rpm to keep it at 82*C). Is this safe to run a lot? I could use the MSI Manual Fan Profile, but the 5970 can get loud(around 60 percent) keeping it around 74*C. This is with all my Antec 1200 fans on high too.
 

scooterlibby

Senior member
Feb 28, 2009
752
0
0
I have a similar setup as you. I just set it at 1.16 and was able to get it to 900/1200. I up the fans to 70% though when I game and yes it is loud, but I use headphones.
 

masterkaj

Junior Member
Dec 22, 2007
24
0
66
I have a similar setup as you. I just set it at 1.16 and was able to get it to 900/1200. I up the fans to 70% though when I game and yes it is loud, but I use headphones.
Yeah I use headphones too, but they are open air; not noise cancelling.

What temps you run at? I figure these things could take up to 100*C, so mid 80's during gaming should be fine. I think the fan runs at like 35-40 percent while I play BFBC2 (just using the stock auto fan profile).