An 8 year old version of XP will need significant driver updates for the new hardware platform, you will probably need to at least do a repair install. You will also need to re-activate XP.

One significant problem you will run into will be support for AHCI vs Legacy IDE settings in BIOS for your HDD.

Your existing installation will almost certainly not understand AHCI (XP doesn't ship with AHCI drivers) and in modern MBs the legacy settings give pretty poor performance, especially by comparison to AHCI.

There are ways around this but I'm not going to try to go into it at this kind of distance - it's harder to explain than to do...

Of course, you can elect to run in legacy mode and it will work fine, probably just slowly.

Otherwise, make sure ASUS have XP drivers available.

If it was me, I'd opt for a new machine but specify Win7 - you should still be able to get it and it will understand all the current high performance bits and pieces on the MB. I'd also go for a fairly large HDD - at least 1.5 TB.

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