ck9: cpu doesnt help with graphics ... itld still suck no matter how good a cpu u got
Untrue, because the CPU has to tell the card what to draw.
Think a very high end video card in a machine with a 200mhz P1. Performance _will_ suffer...
Also, it's likely that a server CPU (such as the Opteron - I've never seen an opteron in a 'normal' workstation machine) might not have certain 'special' instructions that can speed some math and graphics operations. (MMX, SSE, 3DNow!, etc)
I could be wrong, but it really wouldn't surprise me.
As for having to rewrite the game, it does depend on how the game is structured, but the biggest factor is probably the operating system's SMP support. Assuming your OS supports SMP, if the game is already multithreaded, you might see a performance increase because the OS can execute the threads in the game process on multiple CPU's (up to 8 in this case, since dual core is pretty much two CPUs on a chip and the operating system and hardware treats it as such)
However, there is still only one video card in the system, and you could still have a bottleneck on the PCI / AGP bus or with the card itself.
Multithreading is also the reason that multiple processors really help on a server system. Most server software is multithreaded (or in some cases, Apache is one big example of this, uses multiple 'child' processes where it forks a new server process when an HTTP request comes in).
Basically these work by running a 'main' thread or process which waits for connections and then forks a child process or spawns a new thread and passes off the work to be done onto this new thread/process.
Anyway, there aren't a lot of games that run multiple threads out there. On single processor CPUs multiple threads for a game results in additional overhead and actually hurts rather than helps performance.
In the case where there is no multithreading (most commercial games since less than 1% of their users are going to have SMP systems), the only performance gain you can get is when the operating system pushes idle / background tasks to another processor (thus the game will have one or more processors almost completely to itself). This brings a minimal speed increase at best, and you probably won't notice any difference.
Moogle: 128 bit PPC processors do exist.
