Since I'll be replacing my motherboard I know I have to regrease/repad the heatsink/proc. I'm unsure though if I should find a thermal pad or use Artic Silver 5(I've never used grease before) I'd also like everyones opinion on Anti-Static workmats? Someone suggested that I replace the stock heatsink/fan on my Athlon64 3700+(San Diego) with a better one but i'm not sure if I should bother though, my main goal overall is stability I don't overclock anything.

Processor: Athlon64 3700+(San Diego)
Motherboard: Asus A8n-Sli premium