Reusing heatsink / fan - will this work?

[Smithore]

Back in 2006, I bought some silent PC components to build a media PC out of spare parts. Last month, I just built a brand new desktop PC (Intel i7), and I want to take my old desktop Alienware PC (AMD 64 4000+), mount it in my media PC case (a Silverstone), and try to make it a little quieter. Specifically, I'm interested in whether I can reuse my heatsink / 120mm fan combo.

Here's what I used to have:
Intel Pentium 4 2.53GHz
Thermalright SI-120 High Performance CPU Cooling Heatsink
- http://www.newegg.com/Product/Product.a ... 6835109123
Silverstone LC17-B ATX Media Center
- http://www.newegg.com/Product/Product.a ... 6811163055

I'd like to keep the case. Can the Termalright SI-120 be mounted on an AMD 64 4000+? With a 120mm fan, can it keep things cool?

Here's what I'd be running if I crammed my old desktop PC parts in my (older) HTPC case:
AMD Athlon 64 4000+ with HyperTransport Technology
Alienware motherboard based on VIA K8T800 Pro chipset
Alienware 460 Watt Max Power Supply

Thanks for the help!