its worked for a year, havnt changed anything, no new hardware, all leads seem ok. It doesnt go in to bios it just starts and hums. Floppy, CD-ROM dont even run, and i dont think its running the hard drive either
Yep, sounds like a faulty power supply unit ! Does the power light still come on and the fan start (as per your original post) ?
As a last resort, you could strip everything out of the PC, re-fit everything and see what happens. I have seen a case once where a graphics card was not seated properly and this was causing the PC not to boot up.