I was thinking of getting a Phenom II 955 and OCing it to around 4Ghz (Hyper 212+), but I don't know performance gain that will yield. Is it worth another $140? My top two uses are gaming (the most demanding game I play is Dirt2, but that will likely change in the next few months, resolution is 1280x1024) and coding/compiling (I dual boot Ubuntu and do a lot of coding and self-compiling of programs. Would it speed it up very much?).
Yes and no. I say yes as it would be an improvement to upgrade as greghome suggested but I say no as in not yet. As long as you can still do what you need to do, I would keep using it until the new cpu lineup hits. The worst thing that will happen is the cpu you want now will get cheaper. The best thing may be your next upgrade may be marginally better than the 955 cpu and you wont be slapping yourself on the noggin wishing you waited a bit longer.
The other con will be the new cpus will require a new motherboard but if the performance gain is good enough it may be worth it...
and the Mobo is an AM3, so there's no need to change the motherboard,
either get a Athlon II x4 640 (100USD) or the Phenom II x4 955BE (140USD)
The Phenom should have more juice overclocked due to it's L3 cache though
I'm saying he will need a new motherboard with the next gen cpu's coming down the turnpike. For now, I would have to agree to go with the Athlon II 640 as I have 3 of these and they perform exceptionally well. If you can't wait to upgrade that would be the best path at this point performance/cost wise...
What if I was thinking of upgrading to, say, a 460 1GB and then OC it to 900 or so if I can? Would my current Athlon II bottleneck that?
On another note, would it be better to get a bigger monitor instead of upgrading the cpu or gpu? Right now I'm using a really old 17" LCD.
Dangit, it looks like if for gaming I want to upgrade one of those three (monitor, cpu, gpu), it won't be worth the investment unless I upgrade the other two. Oh well... I'll probably try to get a new monitor because most of my time on the computer isn't gaming.