If you have arrived here from an external link, Ultimate Boot CD allows you to run floppy-based diagnostic tools from CDROM drives and consolidate as many diagnostic tools as possible into one bootable CD. An experimental feature also allows you to run UBCD from your USB memory stick on newer machines that supports booting from USB devices. Read more about UBCD and the full list of freeware diagnostic tools included here.

*If you live on the cutting edge, a beta version of UBCD V5.0 is now available for testing.

*as702 has contributed an updated version of dosubcd.img for UBCD V4.1.1, including instructions. This is the same version of dosubcd.img that is included in the beta version of UBCD V5.0.

Please note that I do not host the downloads directly due to the sheer amount of bandwidth required and its associated cost. Instead I rely on a network of mirror sites offered and maintained by volunteers. If you find a particular mirror site to be down temporarily, please be patient and try another one.