i have a relatively old pc and i'm looking to upgrade the RAM to 4gb...trouble is, i don't know if the specific ones i want would work with my pc. It's a dell optiplex 320, intel E4700 cpu, 305 watt psu, motherboard has X200 ATI intergrated graphics and 2 memory slots.I've used kingston 1gb ddr2 667mhz with cas latency of 5 and it worked quite well. wanted to know if the above options would work and if not, could someone recommend something good and cheap? and something else, could a sapphire ATI radeon 4670 graphics card work without having to change my psu? thanx.