Hi guys, hoping i can get some help with your knowledge.

I'm currently fixing a pc which was "dead" for someone. needed a new PSU (tested a diffrent psu and turned on fine) But now ive put in a new PSU the pc turns on (all the fans and the motherboard LED work) as soon as the power cable is plugged in, but it never gets any further IE: doesnt boot up!! and i cant turn it off by the power button either. i dont know much about the pc and im a bit stumped. the most info i can give specs wise is:
Asus motherboard (775 ??? socket, the one with a similar number anyway!)
SATA hard drive
520W psu.
Sorry its not a lot of info, but i really need this fixed, as it could be the decision changing vote on getting a job

Can you test with another gfx-card?
Anything in the monitor?
Test with another motherborad?
Does it bleep any warning sounds?

I had a somewhat same problem a year ago. My mb died suddenly and I tried switching everything except the mb. In the end I said "The hell with this, I'll just buy a new set" Worked fine since

Check the RAM.

Vain

Thanks for the tips guys.
i know power is working, CD drive light stays on when the pc turns on. there are no system beeps at all on boot.
gfx is a chip not a card, monitor is fine.cant try another motherboard.
I shall check the ram when i get a chance, anything im actually looking for on/in it?

maybe resetting the bios could help. (remove the "button" battery from the motherboard for a few mins to reset the bios. then put the battery back in and reboot. you should be trying to get the system to post so if i were you, i would disconnect all drives and i would also remove the ram. when you power on the system, you should get an memory related beep error. this should show that the mobo is working (ish). place one stick of ram into the mobo and power it up again. kepp adding only one device at a time and power on each time. it should take 30-45 mins to do. but but you should be able to spot problems better this way.

check the heat sink is fitted correctly on the cpu and that the fan starts up as soon as you press the power on button

i dont even press the power on button and it turns on! (with any PSU) just boots as soon as the cable is put in

remove the "power" jumper that connects the power switch to the motherboard. but then you would have to make a connection to the two pins the a flat head screwdriver if you wanted to switch it on again.

dadge, will that just be a one off "fix" til i can find the fault or something that will need to be done every time? as i dont think the people at the company will enjoy using screwdrivers to short circuit switches every day.

it was a trick i learned in a cumputer repair shop. it is only to save disconnecting and reconnecting the button every time you want to start the machine. it sounds like it is either wired wrong (to the mobo)or is broken. has the button ever worked like it was supposed to?

not sure, ive been given it to fix. supposedly there was a "bang noise" whilst it was off
the MB does seem very high off the case and seems to flex lots, maybe its just had the circuit boards broken in some way?

it might, but you can only find out with a replacement board. if you can take the mobo out of the chasis and have a smell round it, you might be able to smell burning.

yeah, no replacement mobo about, and i dont have the money to just "guess" at problems. anyway, il take the sugestions on board and give it a try over the week.

Well.. can't you test with your own mb?

not unless u found a way to fit socket 775's in a socket A mobo

new update:

even with the power and reset jumpers unplugged the pc turns on asd soon as the psu is switched on! any ideas?

mine did that..replaced the motherboard and all was fine again..not saying that its that but could be it

untill 2 days later the church next too my house got struck by lightening and pow...goodbye motherboard and cpu and gcard psu

ahh ok. dont think they are going to enjoy this bill then! new motherboard it is. should be fun to wire in

Motherboards arent very expensive if you just want a normal one..50 euros..going for the big bad mofo of them can cost 300 euros ..

wires are easy...read manual and look where the wires of the reset button hdd light etc go where on the motherboard

be carefull with static electricity !! just grab yer central heating with every component your putting on/in the pc or buy one of them special wristbands

good luck

yeah ive built my pc before, just hate the wiring (mobo and case didnt match up 100% had to send it to someone in the end)

EDIT: stupid q, changing motherboards mean ill need to re-install windows? wil i need to reformat or can i get thru it another way? as i dont have disks and its not my pc.

ah alright my old pc had that..
ive just modified my backplate
drilled a few holes and presto it fits
love drilling holes in new pc cases



Edit if you can get the same motherboard it should be fine..
if not then yep windows should be reinstalled too get no conflicts etc
you can try it without though ..but dont think thats gonna work

wasnt the backplate not matching, the jumpers wouldnt fit!

As for windows, im not sure what model mobo it is, i can give it a go tho. ill let you know how i get on, thanks