I posted my rig a few minutes ago in on of the threads and would like to get some expert opinions about what I should upgrade to

I don't want to spend any more than 400$

Here are my current parts:

#ABIT ab9 pro intel p965 chipset serial ata300 atx form factor 1xpci-e(x16)/2xpci-e(x1)/2xpci/4xddr2 w/sata2 raid,dual lan(gb),usb 2.0 & audio
CORE 2 DUO E6420 2.13G (1066Mhz)
2 CRUCIAL 2GB DDR2 667
EVGA 320-P2-N817-AR Geforce 8800 gts KO 320mb ddr3 w/ acs3

Right now I can run the new total war on pretty high detail, but the loading is a bit slow

I've been thinking about upgrading the processor and the gpu, but, yeah, lemme know what you think.

No hurry to upgrade your CPU in my opinion. Do it in a year or two.

GPU I'd get a 4870 1GB at $125. Not sure what it costs in America, maybe more.

The only CPUs worth upgrading to (E8400, Q8400, Core i5, X4 620 etc.) either require a new motherboard or are too expensive to justify the small gain you'd see.

I'm not sure you'd notice much of a difference from an 8800GTS to a 4870. Perhaps a $259 HD5850?

If you're ever constrained on RAM, maybe 4GB of DDR2-1066 or something? But if you're not hitting the 2GB limit it's not worth spending to upgrade.

Is that price confirmed? If yes, then I agree.

Buy a Radeon HD 5850 immediately.

What limit?

Do your running applications go over 2GB of RAM use?

I dunno, I have 4GB and my Ram meter generally gets to 90% or so

Empire Total War will always be slow.

I good sound card can reduce the load on the system memory and CPU. I noticed a 5 FPS increase just from adding a X-Fi with 64mb of memory. Most people look over this because almost all motherboards come with a sound chip. The problem with these chips is that they use the system memory and a portion of the CPU for processing. Getting a sound card eliminates this.

Also, you said the loading was slow,

You could get a WD Raptor, or get two of them and RAID 0. That will cut your loading time.

http://www.newegg.com/Product/Product.aspx?Item=N82E16822136296&nm_mc=OTC-Froogle&cm_mmc=OTC-Froogle-_-Hard+Drives-_-Western+Digital-_-22136296