I'm running, what I think, an AMD Athlon 64. Well, after looking into buying a new video card, I realize I don't have any PCI-E slots for the new GeForce 8600 GT; I only have on AGP and like 4 or 5 PCI slots. Now, I know to fix this I need a new mother board. But the problem is, after looking at my manual for my motherboard and running some diagnostics, I just can't figure out exactly what I have. I have a board running with 939 connections for my processor. Now, if that's true, that means I have a dual core Opteron. But after running the test, and thinking back to when I bought this, it's saying I have an Athlon. What gives? If my board only supports this Opteron, wouldn't my computer not be working at the moment? Now, the board creator says if I updated my BIOSes version that my processor might work on this board. But the problem is, I just need to find out what the fuck processor I have, so when I buy this new board I don't have to blow any money on a processor.

This is what Belarc gives me:
Processor Main Circuit Board
2.40 gigahertz AMD Athlon 64
64 kilobyte primary memory cache
512 kilobyte secondary memory cache
Board: ASUSTeK Computer Inc. A8V Deluxe Rev 1.xx
Bus Clock: 200 megahertz
BIOS: American Megatrends Inc. 1009.007 12/22/2004

Now, I have an ASUS board, and according to what I've looked into, an Athlon running on the 939 board. FFS, I just want a new video card, but apparently I need a new motherboard with PCI-E slots. So, yeah, any suggestions on how to find out what exact processor I have before stripping this thing down? I'd rather be confident in buying a new board AND video card rather than having to return things and get into over-the-phone arguments.