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Rounding error during Prime95 -- up RAM voltage?

Last response: in Overclocking
July 1, 2011 12:21:05 PM

I have an i5 2500k that I started to OC. I also have 2x Gskill Ripjaws DDR3 1600 4GB RAM.

I have started to overclock and the CPU is stable through intelburntest high 25x and Prime95 using small EFT @ 4.4Ghz + 1.280V. However, when I run a blend test I see rounding errors. From what I've read these are errors associated with the RAM. Do I need to up the voltage? They're 1.5V sticks.. here are my settings (what the package said to do..):

1.5V - 9 -9 - 9 - 24 - 2t

a c 239 K Overclocking
July 1, 2011 12:50:14 PM

first test your ram with memtest86+, if result good you can try to do it , only small raise at 1.58 -1.60v and max 1.65v don't over. Test again
a b K Overclocking
July 1, 2011 2:39:54 PM

I've seen rounding errors with insufficient CPU voltage as well, so that's a possibility.

Don't increase the RAM voltage quite yet. You shouldn't have to do that unless you have four RAM sticks.

Do this first: Check your VTT/VCCIO voltage -- if it's not 1.15v, increase it to that.

If it still gives errors, increase the CPU voltage to at least 1.3v and try again.
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July 1, 2011 3:41:41 PM

I up'd it to 1.15V (was 1.05V) and still saw a blue screen.

The thing that perplexes me the most is the fact that the CPU tests pass with flying colors but once I start the blend, I see rounding errors or blue screens. I've increased the voltage and it's hanging out around 1.288 - 1.296 during a blend. I ran it for around 30 minutes and it was fine. I'll do a longer test once I'm away from the machine.
July 2, 2011 11:48:32 AM

I ran Prime95 last night and after two hours it saw a rounding error again and then BSOD: 124.

I'll increase the Vcore again... it's just weird that on any other CPU test it passes, but when I run this blend it constantly fails..
a c 197 K Overclocking
July 2, 2011 12:47:11 PM

You can also try relaxing the memory timings.
July 2, 2011 6:15:16 PM

How should I relax the timings?

I ran another test which had no issues for over two hours... it blue screened again.

I've increased the voltage from 1.28 to 1.31... CPU is absolutely fine in small-eft/intelburntest still...