No post, no bios - but very rarely they show up

[zzattack]

My monitor gets no signal at all (that doesn't mean the monitor says no signal, it just keeps itself in stand-by mode). My first guess was a broken AGP slot, but PCI videocards give equal results.

I have an ASUS P4B533 mobo. All hardware seems fine, pc stripped down to mobo, agp videocard, ram, psu, fans. HDD and fans start. Tried to reset the CMOS. After doing that, and trying to boot a few times, BIOS screen popped up asking me the processor speed. I turn the thing off, plug in a keyboard hoping for another BIOS screen, but I don't get it.

I get my USB keyboard ready (plug and play right) and after trying another 100 times to boot up I get another post, then BIOS screen. Asks me for processor speed again, I plug in the USB keyboard and the screen becomes distorted (not sure if distorted is the word, anyway, as if an corrupt image file is displayed, there's wrong coloured bars all over the place).

When I got those post/bios screens, I didn't change the configuration from what I tried before. It seemed completely random to me. Any ideas on how to fix this? Thanks in advance and sorry for my poor English.

 

[Nodsu]

When you get this black screen, have you tried the reset button? Any obvious damage in the system like bad capacitors or funny smell from the PSU?

It is probably some bad component.. You should just start replacing them one by one - PSU, RAM, CPU, motherboard. Replace as in borrow bits from your friends or take the system to a repair shop where they have stuff lying around to try out

 

[zzattack]

When you get this black screen, have you tried the reset button? Any obvious damage in the system like bad capacitors or funny smell from the PSU?

Nothing happens. PSU is fine.

It is probably some bad component.. You should just start replacing them one by one - PSU, RAM, CPU, motherboard. Replace as in borrow bits from your friends or take the system to a repair shop where they have stuff lying around to try out

Only CPU and mobo are left. I can't replace them easily

 

[Tedster]

https://www.techspot.com/vb/newintopic53866.html

 

[zzattack]

I solved it by unclipping the right clip that make the fan stay in place. After doing that, there was only the problem "the system intruded, chassis opened or tempered before. please check the system". I put a jumper on the motherboard that disables this check and it seems fine... but is this safe?