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Old April 8th 17, 03:51 AM posted to alt.comp.hardware.overclocking
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Default Overclock 6700K Max Temps Prime95 Small FFT

On 2017-04-06 23:03, ~misfit~ wrote:

Alright, I tested the PC with Prime95 again, after having redone the
TIM and reseated the CPU - Same results; Prime95 (the latest
version) can make some cores climb to 94C for some tests; we're still
hovering at around 80C in OCCT's CPU test. One thing that HAS changed
is that OCCT crashes the first time I run it and start the CPU test.
Run it again, no matter how many times you like, and it works fine,
but start it for the first time that day and it crashes. So the
situation is actually worse than before. [...]

I haven't been following your progress but from that last bit you wrote it
sounds to me like the factory TIM between the CPU proper and its IHS
(Integrated Heat Spreader) could be faulty. Apparently it's not that
uncommon a thing...

Quite possible. For CERTAIN de-lidding would make this CPU run much
cooler, but I'm not going there lol. Thunderbird crashed again upon
starting by the way, so I now had a few crashes of applications "upon
starting" which told me LLC was not boosting voltage fast enough. So I
changed by base voltage from 1.300 - 1.310 (and kept LLC @ Level 6).
This has the effect that unless the CPU is doing absolutely nothing (and
running Windows is /something/) then it runs at 1.328v (instead of
1.312v as before). So far so good. The downside of course is that if I
run Prime95 v28 small FFT I now see a Max Temp of 97C because the volts
boost-up to 1.360v. I installed the recommended Prime 95 (v26) and I
stay around 80C on small FFT's - v28 uses FMA3/Avx and together with a
high LLC it means a lot of energy is used. I tried LLC @ 5 but then LLC
*lowers* the voltage when the CPU gets really busy. That's what LLC is
supposed to be for actually, but it doesn't work when you overclock.

I agree with you my CPU sample isn't great. The best overclock I get
without boosting volts too much, like I am doing now, is 4400MHz. At
that speed all I need is 1.260v base volts (an increase of 0.010v) and
LLC @ 7. Getting 4500MHz stable requires a lot more power.

If I become unstable as the years go by, or if I discover that I can't
encode a movie or play a game without the CPU climbing to 95C then I
will just fall back to 4400MHz.

Best Regards,

! _\|/_ Sylvain /
! (o o) Memberavid-Suzuki-Fdn/EFF/Red+Cross/SPCA/Planetary-Society
oO-( )-Oo Soon to be a major motion picture!