Hello everybody I have a HP Media Center PC model a1357c. I researched and found a compatible processor upgrade for an insane amount of money. 200MHz more speed for $112 isn't going to happen. The upgraded processor is AMD Athlon 64 X2 4800+ (clocked to 2.4GHz per core). However, I found another processor, AMD Opteron 180 which is the same socket (939), and is clocked at the same speed per core and is about $90 less. After a little research I learned there are some differences between the Opteron and the Athlon, primarily that the Opteron is the "server" version of the Athlon (it of course being the "Desktop" version). My question is if I were to buy the $20 Opteron processor; would it work with the machine I've described above? I honestly do not think it would (based on my sources reading that the Opteron 180 does not have support for Un-Buffered RAM; which the board takes), but I figured I'd ask to make sure. And just to expand my knowledge on the subject, why or why wouldn't it be compatible?