How much space does XP need?

Can someone give me a ballpark figure? iv picked up a copy of XP from ebay for my parents computer (as they have lost the original disks and its borked to the point where only a format will do) but i want to test it on my machine first to check its not dodgy, can anyone remember roughly how much space i need to allocate to the new partition to get it on there?

edit: never mind i cant do a dual boot anyway dont have the right SATA drivers and no floppy disk drive

If your PC is set to AHCI you can set it to IDE before you boot the XP disk then set it back to AHCI after to boot back into Win 7.

The XP came on a floppy?

Here's a snip of the disk space of my fully patched 32-bit XP Pro SP3.

the disk starts, then just after "windows is starting setup" it bluescreens, i changed the HDD mode to SATA (dont have IDE im guessing their the same thing in this regard?) and slipstreamed the drivers into an iso but its still bluescreening

no the floppy bit was to do with the loading SATA drivers tutorial, but gregrocker supplied a link on how to slipstream them, still not working though

You don't have an AHCI option in the BIOS under something like "storage settings"?

AHCI : Enable in Windows 7 / Vista

under the Integrated Peripherals>HDD>AHCI bit of my BIOS i have 3 options, SATA, RAID, and AHCI, the default setting was AHCI, if i change it to SATA it still bluescreens and obviously RAID just refuses to work full stop because i dont have a raid array

Do you have the BIOS set to "no restart on system failure" so you can view the error code.

the error code is 0x00007B according to: Advanced troubleshooting for "Stop 0x0000007B" errors in Windows XP its to do with sata controllers, i downloaded the XP drivers directly from Nvidia, and no luck

thats not a bad idea iseeu i might do that later