Could be a false positive. If you want to download official (leaked) 174.20 drivers for XP 32-bit, try here:
http://downloads.guru3d.com/ForceWar...load-1866.html
Some say they've had more success with the 174.20 then the 174.16, even if they're non-tweaked.
Oh, and here's for Vista 32-bit too. No 64-bit version of these yet, sadly.
http://downloads.guru3d.com/ForceWar...load-1863.html