Any Overclocked Systems?
 

Hello everyone,

I was just wondering how many of you have overclocked systems that participate in the GIMPS?

1 i750 here using GigaBytes standard OC utility

2.66 ==> 3.2

A friend of mine had a Pentium 4 box liquid cooled, at about 4.6 GHz

Sadly, heavy overclocked machines don't behave very well with highly optimized number crunching programs... :smile:

Luigi

I have a Q6600 overclocked from 2.4 > 2.8 GHz; a relatively mild overclock, but enough to give a sizeable output boost and not so much that it can't be comfortably cooled on air with a $15 heatsink. :smile: It doesn't usually work on GIMPS per se, but is usually running PRPnet clients for some of the smaller projects hosted in this forum (No Prime Left Behind and Conjectures 'R Us).

I overclock my Q6600 to 3.0Ghz occasionally when I am only doing sieving. I am pretty certain it is prime95 stable at that normally but I haven't retested it at that since I added a graphics card and added more memory.

I have two overclocked computers running LL tests: a Core i7 920 overclocked from 2.67 to 3.00 GHz, and a Core i5 760 overclocked from 2.80 to 3.00 GHz. I also had a Core i5 750 overclocked from 2.66 to 2.80 GHz, but somehow it was reset to default speed in January, and I'll wait until I have had time to install a better heat sink until I overclock it again.

One thing to remember if you overclock is that if the computer makes a single error in the 6 week long computation, the result is wrong. So if you overclock it to the limit, lower the overclock quite a bit, and remember to vacuum your air filters regularly (especially in the summer).

Core i5 750 from 2.66 GHz to 3.6 GHz without voltage increase (double checks okay). Starts making Prime95 roundoff errors seldomly at 3.8 GHz.

Waiting for 2012 Ivy Bridge with 3D transistors reaching 5 GHz air-cooled. ;-)

I have 4 overclocked quads. It takes a fair amount of work/maintenance and the power bill is crazy.

[QUOTE=ET_;264967]
Sadly, heavy overclocked machines don't behave very well with highly optimized number crunching programs... :smile:

Luigi[/QUOTE]

I don't know about that Luigi. My 5.27 GHz i7-980X does very well.


It scored 13.32 on CineBench 11.5 which you can see 1:55 into the video.

[QUOTE=patrik;264980]
One thing to remember if you overclock is that if the computer makes a single error in the 6 week long computation, the result is wrong. [/QUOTE]

Understood, and I agree with that.

Most of the "problems" I found when overclocking and doing heavy RAM crunching reside in the RAM timings. If you painstakingly adjust the timings to the "sweet spot," you can still get nice overclocks.

Right now I am using my 3.9 GHz i7-870 (HT off, 4 cores) to participate in the GIMPS. It turns in a performance that is slightly better than a stock Gulftown (i7-980X @ 3.33 GHz) if you constrain the Gulftown to only 4 cores.

I've got an i7 920 OC'd to 4 GHz with HT under water. I don't use it for straight up GIMPS work, but do use it for related things. OBD TFing for example (which will eventually be folded into GIMPS).