920 overclock problem

Naff8000 · 19 Nov 2009 at 05:17

I've stabilised at 3.8ghz, or at least it seems so after 30 min tests on small and blend. Yet now it's often resetting back to stock when I turn on the pc, it begins to post then resets itself and it's back at stock when I get in windows. When I go in the bios it gives me the warning sign that the overclock has failed.

The same happens at 3.6ghz, although it seems ok at 3.4. Anyone know what this might be?

CPU Clock ratio: 20x
QPI Link speed: x36
BLCK: 190mhz
Vcore: 1.3
QPI/Vtt Voltage: 1.355
DRAM: 1.64V

Naff8000 · 19 Nov 2009 at 15:53

Well anything less than 1.355 and it doesn't last 7 minutes in stress tests

Naff8000 · 19 Nov 2009 at 21:27

My uncore multi is x20. I've never touched ram timings before. I spent 3 hours on this the other day, the pc isn't interested unless QPI is 1.355. At 1.25 it doesn't post, whatever the vcore (tried up to 1.425) At 1.3 QPI it didn't last 20 seconds in prime 95, 1.325 about 3 mins. Progressively on to 1.355 where it lasted the full 30 mins.

Naff8000 · 19 Nov 2009 at 21:30

Using a TRUE 120 cooler. Load temps after 30 mins we're 68c

Naff8000 · 19 Nov 2009 at 21:35

DRAM Timing selectable set to auto
mem multiplier is 8.0

Naff8000 · 20 Nov 2009 at 14:37

Ah thanks. The auto had the timings set to 7-7-7-16. I'm doing a small fft test right now with vcore: 1.3 and QPI: 1.295 and uncore at 16x @ 3.8ghz. Everything seems fine after 8 mins so far with a high temp of 68c.