AMD Opteron Stock Cooler/Good Enough For OCing??

When you overclock you dont just say "i want x speed" you first have to figure if it will reach that speed, by upping bit by bit, and chances are it wont go far, and chances are it might go really far - luck of the draw, and opterons have more headroom and luck then the athlons.

Aftermarket cooler - it would help keep the temps down, but you might get away without it depending on how much extra vcore (if any) you need to get there.

Good luck

Going from 2.2 to 2.6 w/ an Athlon and Opteron is very easily obtainable on Socket 939. If it's Socket 940, because of the ECC RAM and lack of RAM Dividers in BIOS's of s940's, you won't be OCing s940 opterons much, but I have done a stable OC of a 2.4Ghz Opteron 64 Socket 940 to 2.8Ghz w/ ECC RAM Overclocked using an aftermark HSF. I used default voltage for CPU of 1.4v and temps were 28c idle and 34c load w/ Thermaltake Venus s940 HSF. Your stock heatsink and fan is plenty for that 2.2 to 2.6, if you want to get 2.8 or above, I recommend an aftermarket heatsink and fan.

~~Mad Mod Mike, pimpin' the world 1 rig at a time