Need opinions on upgrading

Unless you're using 64-bit Windows, adding to your RAM is pointless... and PC6400 is still performs pretty well, so don't feel too bad about the lack of DDR3 support.

I'd concentrate on upgrading your GPU and hard disk. With your motherboard however, your GPU upgrade options are limited. How does a 1GB 9500GT sound? It's currently the best I've found at NewEgg that fits into a PCI x16 slot.

And of course you don't have to ditch your old drive... why not just add a 1GB Caviar black to your system?

I am def adding a 1tb WD drive tot eh system to go along with the 300gb I have now.

The video card was my main concern at first. the more i looked into video cards that got me into possibly upgrading the CPU/MB. I was right off the bat attracted to the Radeon 5850/5870 cards (I know they are PCIe 2.0 which my mb doesn't support) but i have always been a Nvida owner and wasn't sure about jumping over to an ATI card even though people love them. So looking into these newer Video cards (even the GTX cards) I'd have to upgrade my MB if I do that might as well upgrade my CPU if I am going to see noticeable performance boost form my current CPU to say a phenom II x4 945 or 955.

On Newegg I seen I can get a Phenom II x4 955 and a Asus M4A79XTD EVO (seems like a solid board unless there is better for same or less price) for $275 range. Seems like a reasonable price if it will clearly out perform my current cpu and give me the ability to put a beast Video card into it. Also would def want to change my case for better cooling (love how that Antec twelve hundred case looks) also not sure what aftermarket heatsink/fan work well with these cpu's. I know my current heatsink/fan is massive think it's by Rosewill and fits on my socket AM2 now and works amazingly.

I'm just not sure which cpu I like better the 955 BE 125w or the 945 95w.

@mi1ez my current PSU is a Rosewill RP550-2 550w with dual 12v rails the output is rated at +3.3V@30A, +5V@50A, +12V1@18A, +12V2@18A, -12V@1A, +5VSB@2.5A.

Since I am getting a new Video card and I am going to upgrade the CPU/MB I was going to upgrade the case/PSU also for better cooling. I liked the Antec twelve hundred case and the PSU is going to be the Antec CP-850 850w output on that is rated +3.3V@24A,+5V@30A,+12V1@22A,+12V2@22A,+12V3@25A, +12V4@25A,-12V@0.6A,+5VSB@3.0A

I'm just trying to figure out right now if I am going to go with the 945 95w non black edition or the 955 12w Black edition CPU and which Mother board I am going to pair it up with and what Heatsink/fan would be optimal for cooling (not really up to get into water cooling options)