My boyfriend has a Sony Vaio desktop that attempts to run Windows XP on 512 MB of RAM. I ordered him the correct 1 GB upgrade kit as two 512 MB DIMMs.

I looked at the motherboard, and it's composed of two banks of two slots each. The existing configuration has one 256 MB DIMM in one slot in each of the two banks.

My question is how I should install the new upgrade to give him 1.5 GB of RAM. I had always thought that identical DIMMs should be installed in all slots of a given bank, not split as his are. Should I just go with what Sony has and put a 512 and a 256 in each bank, or should I move them so that each bank has two identical DIMMs in it? I lean to the former since that's how Sony made it, but I'm not quite sure.

I figure some of the tech gurus here will have an easy answer. Thanks!