Need Help with an Upgrade

[rhettdb2005]

So I am looking at upgrading my video card to the new 8800GT (assuming I can get my hands on one). Here's the system

Dimension 9100
Pentium 4 630 (clocked at 3GHz, 800FSB)
3 GB DDR2 (2x512 @533Mhz and 2x1GB @ 600Mhz)
ATI X850 XT 256MB pci-e Card
Stock 375W Power Supply

I also will be installing vista when I get the new video card.

My main concerns are these:

1) Will my power supply be enough? I know it is slightly below recommended for the 8800s, but I have read elsewhere that the dell PSUs give enough power...
2) How constrained will I be because of the Pentium 4? Would I be better off getting a cheaper video card? I don't have the money to do a full upgrade at this point (ie new motherboard/CPU), but I am looking to do a full rebuild in a years time. I am thinking the benefit to getting the 8800GT is that when I do that MB/processor upgrade I could have the option to get another 8800GT and run SLI.

Thanks for your help, I appreciate it! Any other thoughts are welcome.

EDIT: Realized it might be helpful to say what I am looking to play with this: mainly bioshock, crysis, HL2, oblivion, etc.

 

[practor]

The 8800 GT is a nice card, however its running the same specs as the old Geforce Ti4200 back in early 2000>2002. Your APX PSU? at 375W, my opinion if it was me to upgrade but some others may differ.

PS: You dont need to SLI really for better graphs for gaming. If your going to Video edit etc then fine.

For the same money you can buy the I chill 8600 GTS which is factory clocked. EG core 710 MHz Mem 2100MHz I think the 8800 is 600 or more.

I have that card and I play all the games you mentioned with NP at all..

 

[rhettdb2005]

If I do go to get a new PSU, are there any compatibility problems I should be aware of? Thanks for the suggestions! Would love to hear any other thoughts or opinions.

As for the 8600GTS I would be concerned about the size of the card and how well it will fit. I'll look into it though