Before I get flamed........ Several of the USB HD manufacturers used to include a chipset that allowed XP to go beyond the 2 TB limit, It has been removed (likely at MS's request, though I can't prove that.) I found out the hard way; by buying several.
Here is a link to an article from Seagate, that while in corporate speak it does verify my statement; also the fact that I have around 10 of them that work with XP verifies it!
My adds on Craig's list mostly get responses somewhat like "you are an idiot. XP has a 2TB limit"; which is why I posted the above first.
Now that we've got that out of the way, does anyone know where I can get a few of these drives? Brand is largely immaterial at this point. Used, mint is ok as long as it's only been plugged into an XP box (newer os's will erase the XP MBR).
I would guess from my experiences that these changes occurred about a year ago. If you have an unwrapped 3 year old USB Hard drive (or know a source) , I want it!
I've even called manufacturers, been assured they were still using the old chip set, & bought it to learn they weren't (manufacturer's have not been real up front about this; even the Seagate link was very hard to find)
Several of my drives are dieing due to heat (I'm told the MBR chipset generates more heat than a standard hard drive) & old age.
At the right price, I could want up to 5. Bottom line, is they MUST work with XP.