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Old 2004-01-30, 19:03   #4
nomadicus's Avatar
Jan 2003
North Carolina

3668 Posts

Originally Posted by Unregistered
Thanks for your quick reply ;)
You are welcome.
Actually I ran 2 instances with the affinity option on
Someone can correct me, but I believe affinity for two instances of prime95 each on their own virtual processor doesn't make any significant difference thruput wise. They run half as fast, but do twice the work . . .
just to be sure my system is being stress tested at 100% but that made my system go instable..
How do you mean unstable? the machine ran slowly or had a hardware error? If the former, you may be paging/swapping heavily and need to reduce the amount of memory prime95 can use. If the later, most likely it is a hardware problem that needs attention.
but maybe that isn't so weird since it was then running at 200% since 50% equals 100% cpu load right?
HT means two virtual CPUs and
50% means 100% of the physical CPU and
50% + 50% means 100% of the physical CPU but
each 50% runs roughly half as fast and
the thruput is very dependent on the optimization, or,
rather, the lack of optimizations, of the code, therefore,
prime95 doesn't really take advantage of HT one way or the other when it comes to LL. In fact, others have reported that 2 LL's run less efficiently (a couple percent?) on HT and Windows XP.

I know it is rather confusing but HT is meant to take advantage of unused pipeline cycles. Prime95 is coded to fill the P4's pipeline and keep it full as possible; therefore, all of my prime95/P4/LL machines have HT turned off or else I would go .
Originally Posted by Unregistered
Do you recommend the Blend option in the torture test btw? To see what my system is capable of?
I'll let someone else answer that. I haven't used the new torture test very much.
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