A Celeron 2.4 does fuck all operations per clock when compared to an Athlon 2800+. It is all about architecture. A 2800+ is comparable to a P4 2.8|533MHz FSB and it will perform significantly better than his OCed Celeron. It should, it costs a shit load more. AMD have proven that clock speed isn't everything.
A 9600XT is also way way waayyyy better than an FX5600. Take that into account aswell, it is a huge performance difference.
OnT: 1GB sure does help alot. You should get a 2.6 at 800 FSB and OC the crap out of it. Can get them up around 3.1-3.4 with air cooling, 3.0 is safe with stock cooling. You could use your RAM to the best of its abilities that way. Your current FPS are limited by your GFX card a little aswell. I have a Pixelview FX5600U, the damn thing comes stock OCed with 256MB DDR2 and I still average 20-25 FPS in an uber zerg with eye candy off, with a P4 3.0 OCed to 3.4|1GB DDR400 running 5:4 (not happy about that, need faster RAM ffs). All in all, looks like a good upgrade, can play in any circumstance.
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