How long before my tech becomes obsolete?

Processor: AMD Athlon X2 Dual Core Processor 4400+ 2.21GHz
Ram:1GB
Graphics Card:x1600pro 512MB PCI x16
Motherboard:ASUS A8N32-SLI Deluxe Socket 939 NVIDIA nForce SPP 100 ATX AMD Motherboard

Obsolete for what?

I've got a 4 year old Athlon XP 1800 w/ 256 (now 768) RAM and it's been fine for browsing  the web, emailing, programming, listening to music, watching videos and writing documents. On the other hand, for contemporary games it's pretty much completely useless!

Your PC will probably be fine for 4-5 years for most stuff. For games maybe a couple of years?

(Annoyingly tho on mine the new Creative Suite won't install because a few of the apps require SSE3 instructions. A new system may be happening soon.)