I've just collected the beta of version 21, to run on my P4 at home.
When I run it on my K62/333 laptop (which I was using as a portable disc
having downloaded the beta at college), the self-test tries to test M5242881
with a 256k FFT, gives an excess-roundoff-error message and dies; this is
presumably a bug. I did set the processor type to K6.
When I run it on the P4, the self-test checks a set of thirty or so
exponents with a 320k FFT length, and then does it again, and again, until
it's run a total of 306 tests. This surprised me slightly; I was expecting
it to exercise all the FFT lengths with random exponents to check for
edge-conditions in the new P4 code. Is the self-test in fact just to check
that there's not something in the CPU which goes glitchy when running
flat-out SSE2 code for hours on end?
The P4's PSU fan seems to step up a gear when I've been running Prime95 for
a few hours, though the CPU temperature reported by Intel Active Monitor on
my D850GB board doesn't go about 46C. I suspect the P4 probably runs too hot
for it to be possible to build a really quiet solution, but does anyone have
suggestions? In its current state I'd get no sleep if I left the machine
running overnight, so I'll probably be running Prime95 only if I remember to
set it going when I wake up.
33M ticks per iteration for M5171311, which is 25.8 milliseconds on this
1300MHz machine; so one double-check in that range every 36 hours. That's
about a factor six faster than the P2/350 I just sold, and I recall that
machine as having been at least four times faster than the P90 I had when I
started running Prime95 ... I'll have done noticeably more calculation by
the end of next month than that P90 did during its lifetime.
Tom
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