good, RAM will work for sure but you need to know what FSB you have to put, do a little work, open your system, check what is the speed of the RAM(either by checking in BIOS or removing the RAM and seeing the speed written on side). how many DIMM slots your mobo has got, you still need to check these, and this can be done by you alone
Little ovverhead on this P4i45GV R3.0 and P4i45GV R5.0
so max of 333/266 FSB DDR RAMs is what you can get.
1GB stick would cost you around 1.1K