bit stuck

[Swearwolf]

step dad gave me his pc to fix, being lazy and leaving it to last minute need an easy fix please. gets to the windows7 loading screen then goes no further. cant start in safe mode.it says "couldnt read from one of your devices" or something

[Kieran]

Take everything out that isn't needed. For example:

Remove all hard drives apart from boot drive
Remove all optical drives
Remove all but one RAM stick

Then try and reboot in safe mode. If it works then keep adding components until it stops working again