Getting new CPU have a couple of quetions

[mikesx4911]

Im going to be buying the AMD Phenom II X3 720 2.8GHz really soon, and I just had a couple of questions. My motherboard is a M3A78-EM I need a bios update on it to support this cpu, I went to the manufacturers website and was looking at the bios updates. Im a little confused, some of the updates say they support the new cpu am3 but doesnt say they Improve system stability and performance for certain memory. And I need a update for memory as well because Im running windows 7 and for ram it tells me 4gb is installed but only 3.25gb is available and yes its the 64bit version. Need some suggestions on the bios update, which one should I get? Im planning on buying more ram but it seems like Im capped at 3.25 because its telling me thats how much is available. And my last question is, with the new cpu change, can I use my old fan? My current cpu is AMD ATHLON 64X2 6000+


bios updates
ASUSTeK Computer Inc.-Support-

CPU
Newegg.com - AMD Phenom II X3 720 2.8GHz 3 x 512KB L2 Cache 6MB L3 Cache Socket AM3 95W Triple-Core Black Processor - Processors - Desktops