I want to upgrade my computer and later into a whole new machine.
my pc is a Pentium 4 3.0ghz , 1.5gb ram, LGA775 x925 motherboard , Nvidia 8600gt 256mb PCIe and a 350w power supply.
which should i upgrade first? processor and motherboard or graphics card and power supply?
2 items that will carry over to a new build and still give you an upgrade right now are power supply and graphic card. Get a quality power supply that will handle what you want your new build to have and a graphic card as well. An example might be this HD4850 OC for $140 after rebate http://www.newegg.com/Product/Product.aspx?Item=N82E168...
more then you need for your current build, but good when you upgrade to a new system and/or use crossfire. Yes, the GPU will be bottlenecked by your current CPU, but you're picking these components for the future build.
I've been running far cry 2 with medium settings and runs fairly good.
this is the game I would like to play at high or very high settings doesn't have to be ultra high. do you think a Pentium e5200 wolfdale will increase performance of my 8600gt 256mb or will a ATI HD4830 with Pentium 4 3.0ghz have more performance? which would be best?
Your board probably wont support 45nm chips. You may be able to get a first gen core 2 duo in there. My advice would be to just buy a better video card that you can use when you rebuild your system. No pentium 4 you upgrade to, if you find it, will really help.
I would agree with dirtmountian.
A new PSU and a 4850 work nicely until you can afford to upgrade your entire platform.
Both of his options are great and a PCP&C PSU will last you for quite a long time.
450 Watt or greater power supply with 75 Watt 6-pin PCI Express® power connector recommended (550 Watt and two 6-pin connectors for ATI CrossFireX™ technology in dual mode)
Certified power supplies are recommended. Refer to http://ati.amd.com/certifiedPSU for a list of Certified products.