lumo

hi guys,
i sold my "old" mainboard to a mate, before i took it out it was booting up and beeping if something is incorrect.
yesterday my mate came to my home, and we wanted to install windows on his new rig.
(i put his rig together, but he disassambled it at home to drill some parts out of his tower and reassambled it afterwards.)

now... we tried to start the computer, nothing happened! no beep error messages!
Fans, Harddisks.. all fine and booting up!

i tried:
exchange the beeper
exchange the graphics card (x800 and 3870 tested)
exchange the ram (tried with one of the two sticks (PC6400 G.Skill kit) only, in different banks)
unplugged all drives
took out the additional pci cards (and second gpu)
i even tried it only with CPU mounted and one time without any hardware on...
no beep, always the fans turning on.
even ON/OFF over mainboard works, LED right bottom on mainboard lights up too...
so all seems fine!
btw: i updated bios to fit the Q6600 (and it was already running with such a cpu!)

i'll test the cpu today in another computer to see if its faulty.

any ideas why it does not beep nor boot up? (idk if it does not beep, but i want it to boot! - i do not want my mate to think i am selling trash to him, as it was working before i sold it to him!)

thanks in advance