DirectX 10 and Windows Vista are coming on January 30th, 2007. My current development system consists of: Intel 2.8 Ghz P4, Nvidia Geforce 6800 GT, 1 gig of ram, GA-8PE667 Ultra mb. Right now the only cards that support DirectX 10 are the Nvidia 8800 series (GTS or GTX). These are PCI express cards, and my motherboard is AGP, which means I need to upgrade the video card, motherboard, and CPU to support DirectX 10. The 8800 GTS is a beast of a card. Here is an interesting picture that compares the 8800 with a Voodoo1 obsidian reference board, the first 3D card I ever had.
In addition multicore processors are now available and require a new way of thinking when developing for them. For this reason I have decided to build an entirely new development machine rather than upgrade, and have ordered the following parts (click to see image):
EVGA Geforce 8800 GTS Video card
Intel Core 2 Duo E6400 processor (2.13 Ghz)
Seagate Barracuda 320GB SATA HD
Asus P5W DH Deluxe motherboard
OCZ Gold XTC PC2-6400 RAM
Apevia X-Discovery blue case, 420W PSU (will swap PSU with my current 500W one)
I have also preordered Windows Vista which will be released 2 weeks from now. I won't be developing on the machine until Vista arrives, but I will be putting it together to make sure the components work fine.
I am still waiting for the case to arrive. When it does I'll start putting the components together.