I 'may' have mentioned this before, so apologies if that is the case.
We have been using some Compaq SFF (Small Form Factor) Deskpro PC's for about a year or so now, and have sufficient confidence in them that we have now replaced the 2 machines at work with the same units. We have a total of seven machines now and apart from the memory back-up battery on a couple (CR2032) they have all worked with no problems. They are 1998/1999 manufacture.
These are secondhand ex-corporate user, come with 20gb HDD, floppy, 48X CD drive, Pentium 733/866mhz or some are 1ghz, built in Intel Graphics, Network and Sound, and also has a proper speaker. The latest 3 machines came with brand new keyboard, mouse and mains lead but no monitor, these can be supplied at extra cost if required.
They are currently £65 plus carriage and VAT each. For a back-up machine or even a first machine they are pretty good and very quiet, the CPU fan is temperature controlled. Drivers for the built-in bits can be obtained from Compaq's website, or I have them here to email.
Contact Paul Durkin at IT Dealers in Leeds if interested, he also has a warehouse full of standard desktops and towers and laptops:
snipped-for-privacy@Itdealers.co.uk
We are a very satisfied customer but have no other connection with the company.
Peter