|Instead of buying a new motherboard for your current CPU, you should build a completely new system. |
You can build a Core i3 system for less than $350, or an Athlon II rig for under $300. Both machines would run circles around your old P4. Heck, the fastest Pentium IIIs could embarrass P4s slower than 2.2GHz.
Socket 939 | Dual-core Opteron 185 @ 3.2GHz | 4GB | 1.0TB | Win7 x64
GeForce GTX 460 1GB | X-Fi Ti Pro | A8N32-SLI Deluxe | Antec P182