View Single Post
Old 03-07-09, 05:08 PM   #48
sillyeagle
sillyego
 
sillyeagle's Avatar
 
Join Date: Sep 2005
Location: USA
Posts: 5,394
Default Re: Core i7 Overclocking thread

Quote:
Originally Posted by bob saget View Post
is there a difference between running 8 instances of pi or 4?
When you have HT off it only runs one thread per core, instead of two. Much cooler temps. By turning HT off I was able to gain 200MHz, and despite the increased clock I dropped 10C or more. If you run only 4 instances with HT on it only shows 50% utilization.

For the most part it seems unless stuff is written with HT in mind it's more marketing than anything. Many multithreaded apps show no performance gain, or decreased performance with HT on. A few show a nice gain, but it's rare.

@ meth, I post the other details when I get some time.
__________________
Intel Core i7 920 Nehalem Quad @ 4.0GHz
EVGA GTX 660 SLI @ 1046MHz
OCZ Platinum CL7 6GB
EVGA Intel X58
_____________
A man's dreams are an index to his greatness.
sillyeagle is offline   Reply With Quote