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4GHZ_or_bust
06-25-05, 10:29 PM
I was tweaking my P4 to get a little extra MHz's out but when I had FSB at 110MHz, the CPU temp dropped a whole 10 F (5C) :confused:

When the FSB is at 105 MHz and at 115 MHz, the idle was about 115 F (46C), 124 F (51C) under load but at 110 MHz the idle was 102 F (38C) and under load 116 (46C) F. (note ambient air was 86F to 90F (30-32C) at the time so temp reading is higher than normal)

I used Prime95 stress test for the load and I have verified the overclocking was done correctly when the benchmark showed at 110MHz the result was a bit faster than at 105 but slower than at 115. I'm pretty sure this means the CPU did indeed run a bit faster at 110MHz than at 105 MHz.

The idle and load temp was a bit higher at 120 MHz and more so at 125 MHz. Any idea why the P4 ran a little cooler at 110 MHz than any other speed except at default clocked 100MHz?

2.4GHz (400MHz FSB) P4 with cheap ass water cooling system
10 fans total (I'm deaf so fan noise doesn't bother me :D)
1.5GB DDR
5 HDs total for almost 1TB total capacity

hawtrawkr
06-26-05, 09:44 AM
theres a couple diffrent reasons i can think of this could happen. firstly how much time went between your tests? is it possible the ambient room temps had changed and in turn caused a stair step situation that in turn raised the temps of the pc? was the vcore the same on all 3 settings? also what kind of motherboard was this with? some use a calculation across the die and others use a external probe. needless to say the external probe isnt the most accurate sensor around.

aNTiChRisT
06-26-05, 02:05 PM
It could have been your "Sweet Spot" where voltage, overall circuit resistance etc balanced themselves out... Just something to think about.

~t0m