P-II X4 965 Safe OC Limits?

[someguynamedmatt]

Well, I'm relatively new to the world of overclocking, and I've got a few easy questions I figure I'll ask before I keep on going.

Right now, I've got a brand new MSI 790fx-GD70 Motherboard with an AMD Phenom II x4 965 BE Processor being cooled by a Sunbeam Core Contact Freezer. Right now, it's overclocked to 3.96ghz using an x18 multiplier and a 220mhz FSB speed. I was just wondering if there is a limit to where I should stop increasing my FSB speed, or if there is a better, more efficient way to OC the processor than this.
Any input would be appreciated.
-Matt

 

[sailer]

If you've managed a stable 3.96ghz, you're doing something right. I have a 955 BE on a Crossfire 3 board and can only run a little over 3.6ghz stable 24/7 while folding. Heat is the big problem. I can go higher, but things start getting too hot for my comfort.

Anyway, increasing the FSB also increases the ram speed. That requires more voltage to sustain, and increases the heat from the ram as well. I have not been able to go over a FSB of 220 myself without getting some instability or heat problems from the ram. Altering the cpu/ram speed ratios will help with the problem, but then you give up a bit of performance with the ram.

I've personally found raising the multiplier on my AMD machines as the best route for overclocking. Others will have different experiences using different hardware, no doubt. But for now, if you're able to run your 965 BE under load and stable at 3.96ghz, I think you're doing pretty good and just about at the limit, maybe a bit above it. For more info, here's an Anandtech article:

http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3619
http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3619&p=9

As you might notice, Anandtech ran into a wall at about 4ghz, so you're about there now. You might get a bit higher, but its rather questionable.

 

[someguynamedmatt]

I've been running prime95 for over half an hour, and it's still running as I'm typing right now. I was really suprised at the cooling performance of my CCF. During the entire time, my max temperature topped out at 53c. Yeah, I did have to put a little more power to my corsair ram, but it appears to be stable. It appears as if I've hit the multiplier limit, as trying to go any higher than 18x causes total failure once it hits windows boot screen. I've got it a tiny bit higher by turning up the FSB, but it's barely stable and fails within seconds of running prime95, along with some RAM problems. I'd say I've hit my limit for right now...
Thanks for the response, though. It all really backs up me not being able to pass 3.9