Opterons are the most excellent...and best kept secret in AMD processors, as evidenced by all the X2 and FX threads that ramble on, without mentioning Opty's. Too bad more overclockers don't research the Opty's.
C2D's are 65 nanometers, Opterons and X2's are still 90 nanometers. The overclocking limit for clean 90 nanometer dual core AMD's is about 3.05Ghz on high end air cooling. Check out the following THG article:
And why are they so over clockable, compared to the X2's?
As server / workstation class processors, AMD Opterons and Intel Xeons are yielded from cleaner areas off the same wafer material as desktop CPU's, so they're binned for stability at lower voltages. Consequently, this allows for operation at lower temperatures per clock than desktop CPU's, which is an important consideration for servers. Fortunately for the rest of us, this also makes them the best overclockers.
Is this because they have a different architecture?
Opterons and Xeons are the same architecture as their desktop counterparts. C2D's are a major improvement in architecture over X2's and Opterons, as explained in the above article.
AMD Opteron 1210 Santa Ana 1.8GHz Socket AM2 Dual Core Processor = $175 (newegg)
AMD Athlon 64 X2 3800+ Windsor 2.0GHz Socket AM2 Processor Model = $122 (newegg)
The Opteron is $53 more expensive.
The differences are:
Clock speed: 1.8GHz Opteron VS 2.0GHz Athlon
Cache: 2 x 1MB Opteron VS 2 x 512KB Athlon
Is the Opteron worth it?
I am hoping that the Opteron will overclock higher than the Athlon, or at least equal it?
Is the performance difference noticeable? (cache difference)
I have a 50% overclock on my 3000+ @ 2.7GHz and want to do the same with the Opteron, and judging by this thread, it seems possible