Hardware & Technical Need help ASAP!

Gamersince77 · Oct 13, 2014

I bought a new psu to replace my weak stock 300w psu.

Just fitted it and when I turn on nothing happens, no lights no fan spinning, no beeps no noise no anything.

I have triple checked all the cables.

It's a corsair 750m

Please help
I can't play Elite

Steppas'HQ · Oct 13, 2014

Is fuse in the plug ok? My PSU can blow a 5 amp fuse.

Gamersince77 · Oct 13, 2014

Fuse is fine

Steppas'HQ · Oct 13, 2014

Do you own a multimeter? Does the fan on the PSU itself spin?

Surfinjo · Oct 13, 2014

You need to test the PSU.

Take it out of your computer, place on a table and find a small computer fan and attach it.

Connect power to the PSU.

The fan should spin. Otherwise, you have a duff unit.

Also, with the externnal fan still in, bend a paper clip and plug it into pins 15 and 16. The internal fan should come on.

Note pin 15 will have a green wire and 16 a balck wire

Enride · Oct 13, 2014

This might be rediculous to suggest but:

Some PSUs come with a power switch on the PSU itself, check if yours have one and that its set to on.

Gamersince77 · Oct 13, 2014

Surfinjo said:
You need to test the PSU.

Take it out of your computer, place on a table and find a small computer fan and attach it.

Connect power to the PSU.

The fan should spin. Otherwise, you have a duff unit.

Also, with the externnal fan still in, bend a paper clip and plug it into pins 15 and 16. The internal fan should come on.

Note pin 15 will have a green wire and 16 a balck wire

Thanks for the help but paperclip? I'll electrocute myself

Gamersince77 · Oct 13, 2014

Attackmack said:
This might be rediculous to suggest but:

Some PSUs come with a power switch on the PSU itself, check if yours have one and that its set to on.

No it's not ridiculous and yes I checked, thanks.

Gamersince77 · Oct 13, 2014

Signs of life!!

I just removed and reseated all the cables and now it turns on, all the lights and fans spin. BUT :'(

I get no picture, my monitor on light is showing red rather than green and I get no image. Yes the gpu is plugged in and the power cable plugged into that.

Help?

Gamersince77 · Oct 13, 2014

Put my old psu back in. Turned on and again red light on monitor. No signal.

I'm gutted. Totally gutted

(((((

Surfinjo · Oct 13, 2014

Gamersince77 said:
Thanks for the help but paperclip? I'll electrocute myself

No, the voltages are very low. The biggest you get from a computer PSU is 24 V DC, harmless. The two lines I said to cross carry less than 5V DC. Signal lines to turn on the PSU's internal fan.

Just re-read your last post.

It does sound like the connectors on the Motherboard may have worked loose.

Gamersince77 · Oct 14, 2014

Surfinjo said:
No, the voltages are very low. The biggest you get from a computer PSU is 24 V DC, harmless. The two lines I said to cross carry less than 5V DC. Signal lines to turn on the PSU's internal fan.

Just re-read your last post.

It does sound like the connectors on the Motherboard may have worked loose.

It's not the volts that kill, it's the amps, but anyway I'm too chicken to do that.

I did get the PC to finally POST and I did that by removing the CMOS battery.
Why a new psu would need a bios reset I simply do not know????

Surfinjo · Oct 14, 2014

Gamersince77 said:
It's not the volts that kill, it's the amps, but anyway I'm too chicken to do that.

I did get the PC to finally POST and I did that by removing the CMOS battery.
Why a new psu would need a bios reset I simply do not know????

You've been misled. Sadly, quite common in Electrical studies.

24 Volts is harmless, whatever the current. My PSU pumps out 62 Amps at 12 Volts.

But the old maxim holds true here, if you're not sure, don't do it.