memory speed for msi 775 core duo quad extreme qx9650
I am about to upgrade one of my computers, a systemax, which had a core 2 Quad processor by Intel running at, I believe, 2.2 GHz, and putting in a core 2 Quad extreme qx 9650. The mother board is made by MSI and has a 775 socket. I'm not sure what the current memory speed is, but there are 4 GB of memory in one gigabyte increments (4 sticks). I am running Windows XP Pro service pack three. I need to know what steps are necessary before putting the new chip in, such as whether or not I need to upgrade the bios as well as how to determine the current speed of the memory and what I can do in terms of upgrading the memory to the fastest that I can get. I understand that there may be front side bus issues that need to be resolved (or at least understood) on my part. Can somebody help me? Thanks.