Hi all. Last night I was working on getting a stable 3.8ghz, 200x19. After I got the voltages high enough to be stable, I began reducing them back first vcore, at which point I was stable at 1.27V and then VTT which I got stable at 1.26V (If I remember, might be slightly off but the exact numbers aren't the point...). So I was running Prime95 for quick stability checks, since having the voltages too low I find it'll stop a core or two within the first 3 tests. Then I used LinX for a little bit more checking, plus it's nice to have a speed output.
I had an interesting result. With only changing vcore, I had it at 1.27 and got around 55.5 GFlops on all 5 passes, no errors (as high as 55.8 I think). The theoretical max is (16x3.8) 60.8, so it's only 8.7% off. Really good imo. I then dropped the vcore to 1.26V. Stable in Prime95, moved on to LinX. Almost every pass was in the 51-52 range if stable, and one time it did hit the 55GFlops but it was on a first pass and stopped from an error. I made sure all the apps were closed and processes stopped so it was in the same test conditions. Is this reduction in speed because of throttling perhaps? After trying a few passes with similar results, I went back up to 1.27V vcore and again got stable results at 55.5GFlops.
So can anyone explain what happened? I can't rule out the possibility of background processes but I really don't think that was the issue. So was it throttling? Or maybe there's some "magic" that happens when you have just the right voltages...
Just as a point of interest, I spent a little less time tweaking the voltages at 3.6ghz (200x18) - 1.18V Vcore and 1.17V VTT - and LinX gives me around 9-10% off theoretical max, so I seem to be more efficient at 3.8ghz. I've also read that an odd multiplier gives better results tho so maybe that's why? As in x19 is better than x18.
I had an interesting result. With only changing vcore, I had it at 1.27 and got around 55.5 GFlops on all 5 passes, no errors (as high as 55.8 I think). The theoretical max is (16x3.8) 60.8, so it's only 8.7% off. Really good imo. I then dropped the vcore to 1.26V. Stable in Prime95, moved on to LinX. Almost every pass was in the 51-52 range if stable, and one time it did hit the 55GFlops but it was on a first pass and stopped from an error. I made sure all the apps were closed and processes stopped so it was in the same test conditions. Is this reduction in speed because of throttling perhaps? After trying a few passes with similar results, I went back up to 1.27V vcore and again got stable results at 55.5GFlops.
So can anyone explain what happened? I can't rule out the possibility of background processes but I really don't think that was the issue. So was it throttling? Or maybe there's some "magic" that happens when you have just the right voltages...
Just as a point of interest, I spent a little less time tweaking the voltages at 3.6ghz (200x18) - 1.18V Vcore and 1.17V VTT - and LinX gives me around 9-10% off theoretical max, so I seem to be more efficient at 3.8ghz. I've also read that an odd multiplier gives better results tho so maybe that's why? As in x19 is better than x18.