Fitted New PSU, System Not Booting?

What HSF do you have? Did you touch or remount this? If it's the bolt through type try loosening the screws on the HSF by say half to a quarter turn. Clutching at straws really but have seen others post here where the HSF was so tight it was flexing the mobo resulting in a no boot.

EDIT: Also have you tried firing up the PSU by shorting pins 14 and 15 on the 24 pin connector? Make sure you disconnect the PSU from the mobo, also connect a few fans and even a HDD to the PSU as some won't start unless they detect a load
 
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Do you mean what cooler I have on my CPU - it's a green LED Zalman jobbie - that worked fairly well when the main machine would power on.

I have loosened the screws - but to no avail.
 
On the question of the power button being broken, it seems unlikely seen as though you said the fans do spin up briefly when its pressed, but you can test this by splicing into the two cables and manually shorting them.

I think its more likely that something else got broken on your PC when the previous psu went. I would take everything out that you don’t need to get to the post screen/bios. This includes all drives, and the graphics card if the board has onboard graphics. Then see if it will boot. If not, have a look in your new motherboards manual to see if there is any diagnostic data available. Some boards will have some diodes, or an lcd or some beeps for when the PC won’t boot, and they give you more information about the problem.

Other than that if you are sure you have connected everything right, and that all components are seated correctly, its just a case of replacing each component one by one with a known working alternative until it boots.
 
have you tried a different cable from the mains to psu? i know it sounds strange but i had a problem with a new psu bout 6 months ago and flaffed about for almotst a day before thinking of trying a different lead it it worked, must have knocked the fuse out int he plug
 
In order to rule out faulty components take everything out of the case.

Do a basic build, mobo/cpu/ram/psu on a non conductive surface. Wooden desk will often suffice.

If it does not boot up at this point you have a fault in one of the above components. Test this first and if it works plug in your graphics and have a look at the bois.

If is still works install only these components into your case.

If it does not work when you install it in to your case you know thats where the problem lies.
 
I have just taken it out (again) and performed a light build on the table - graphics, CPU, CPU cooler, RAM (1 stick and 3 sticks) case switches and PSU - Still the same thing happens.

I put it back in just in case the screws were too tight (i.e. only gently tightened them) and same thing happens.

I'm starting to think that when the PSU went - everything went with it - is this possible? :(

I'm going to stop for the day - but any other suggestions will be gratefully recieved.

I have changed fuses and erm, power plugs that go into the PSU. I've even tried changing mains sockets as well :(
 
Does the fan on the PSU start when start the system up. Do you have a fan that you can connect to the PSU via molex to confirm that the PSU starts up?
 
Tried both those things. I don't have a spare PSU to hand unfortunetly.

This is totally taking too much time and I'm sick of bits lying on tables all over my room. I'm going to just send it to the local pc repair shop and get them to attach (I think) a multimeter to it so they can identify the problem. It's just such a PITA atm.:mad::mad::(
 
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