Hi, One of my older computers isn't working. When you try to book the screen remains BLANK. Not even the BIOS startup shows. * HDD is OK - tested it in another PC * PSU leads for the Disk Drives highlighted these 5V & 12V were spot on (couldn't find a spare 3.3V orange however, only one was connected to motherboard) * Video Monitor is fine - tested on another PC * The video monitor was plugged into the on-board video output (i.e. from the motherboard, i.e. not a separate video card). Any suggestions from where to from here? Seems like a problem on the motherboard itself, therefore may not be worth pursing? Thanks in advance

1st reset the bios with the jumper on the motherboard....if that doesn't work try a new battery for bios...if that doesn't work...well then...good luck

Why would resetting the BIOS be necessary? Check that your CPU cooling fan is working properly & that the heatsink isn't all dust clogged. Other than that, the problem probably lies with either the motherboard or the power supply. I'm not actually sure what this means: "PSU leads for the Disk Drives highlighted these 5V & 12V were spot on". If you're saying you checked the voltages & they were within spec, OK, but amperage is the key ingredient. If you need 12v @ 20A & your PSU is so weak that it's only pushing out 12v @ 5A, it's not gonna boot the system. "If my answers frighten you then you should cease asking scary questions" - Jules Winnfield (Samuel L. Jackson) in Pulp Fiction

but re "but amperage is the key ingredient" - how would one verify this? Wouldn't measuring the voltage whilst the power is on be ok?