Thanks for the response Ethan, it was quite helpful.
Yes I did set the type and speed in Prime 95. I wish it was something
obvious like that!
The indexing service was set to manual and is now disabled. No change in
times.
I wasn't aware that running 2 instances on a dual machine would run 30% to
40% slower than a single instance (if I understand you correctly?)
It looks like I may just have to live with it. I am loathe to change those
chips when I am not sure it will help. Also, I'm not even sure I will be
able to find them, even if I was inclined to change them.
I will try your suggestion of running a double check on 1 CPU and LL test on
the other, when these double checks are done.
Thanks again,
Matt
-----Original Message-----
From: Ethan Hansen [mailto:[EMAIL PROTECTED]]
Sent: Sunday, May 06, 2001 8:01 PM
To: [EMAIL PROTECTED]
Subject: RE: Mersenne: Slow CPU's in a Proliant 2500
Matt,
Sorry for raising the obvious, but have you changed both the CPU type and
speed values under the Prime95 Options->CPU menu? Another item to check are
that you have disabled the blasted indexing service. It could explain the
slight CPU time leakage you are seeing. That said, the ratio I typically
see between Prime95 iteration times on a dual processor system with two
instances vs. only one running is in the 1.3-1.4x range; i.e. the difference
between your times of 0.448 and 0.325. I have seen a slight degradation of
iteration time/MHz when upgrading from 500 to 1GHz processors, but not as
much as you report. A way to boost overall throughput is to run double
checking (with it's smaller memory footprint) on one CPU, and primality
tests on the other.
Regards,
Ethan
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Matt
Goodrich
Sent: Sunday, May 06, 2001 5:26 PM
To: [EMAIL PROTECTED]
Subject: Mersenne: Slow CPU's in a Proliant 2500
I have just upgraded a Proliant 2500 from dual PPro 200's to dual Pentium II
333 overdrive processors.
According to Intel's website this is supported. Also Compaq offers this
upgrade.
Now before I upgraded, I was running double check's on 2 exponents, 668xxxx.
I was getting about .515 second iteration times.
Now that I have upgraded, I am only getting .448 second iteration times.
Yes, the affinity is set properly.
[SNIP]
Interesting note here.
If I run just 1 copy of Prime on either CPU I get .325 second iteration
times. It doesn't matter which copy of the program
or which CPU I run it on.
It is only when I run both copies that it slows down to .448 seconds. BTW I
am running Windows 2000 Server with the latest SSD from Compaq.
[SNIP]
Any thoughts or suggestions would be appreciated.
Matt
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