Notice I told him IF he exceeds 3 GB. 3 GB and 3GB 256 MB are very close to the same. 256 MB doesn't make much of a difference. You seem to like to tell people ways to save money that waste a lot of hardware... funny..
Anyway, He says nothing about having software difficulties... I have 7 and I have only run into fixable difficulty with BF2142, and Steam.
If you are talking about difficulty with software, I use a TON of design apps. Photoshop (32 and 64), Gimp, Paint, Premiere Pro, After Effects, 3DS Max (I've used 32 and 64), ZBrush, Illustrator, Softimage, they all work flawlessly AND are more stable because a lot of software developers had to straighten out their sloppy programming from 32 bit. There are a lot less memory leaks, the apps launch faster, and I experience less start up time for the os.
By the way, I don't just use them... I get paid to use them.
Multi-threading has to do with one app using multiple cores, if he likes his computer to multitask it will still make his computer a ton faster to do so. I don't exactly know if you have some sort of beef with intel, or multi core processors, but no one else seems to deny the benefits...
I personally don't think he needs a new processor, but he originally asked about upgrading his system, not IF he should. He wants to. People here are just giving him ways. He asked questions about items, we answered them. He never asked if he needed to, his mind was already set on wanting an upgrade. He also set fourth a budget for people to recommend a build on a new computer, or an extreme upgrade on his old one. Since gutting an entire comp is quite pointless, we recommended a new one since his budget was substantial enough.