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New power supply pc does not start

Last response: in Components
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November 26, 2010 4:43:54 PM

i got a mist 1000w power supply
and when i press the start button the cpufan spins a little and then it doesnt do more than that
the cpu led lights red

More about : power supply start

a c 144 ) Power supply
November 26, 2010 7:15:50 PM

After that:

I have tested the following beeps patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different.

Breadboard - that will help isolate any kind of case problem you might have.
http://www.tomshardware.com/forum/262730-31-breadboardi...

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. You do have a case speaker installed, right? If not, you really, really need one. If your case or motherboard didn't come with a system speaker, you can buy one here:
http://www.cwc-group.com/casp.html

You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU.

Motherboard LED's mean very little. When on, all they are telling you is that the computer os plugged into a live power socket and the PSU is switched.

Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

If no beeps:
At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.
http://www.youtube.com/watch?v=5FWXgQSokF4&feature=yout...

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card. Silence or long single beeps indicate a problem with the memory.

Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.

Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
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a b ) Power supply
November 26, 2010 7:55:22 PM

ive never heard of "mist"
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November 29, 2010 2:10:34 AM

shovenose said:
ive never heard of "mist"


its norwegian product. its got good reputation. and uses japanese kondensators
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a b ) Power supply
November 29, 2010 4:13:44 AM

have you connected the CPU power connector??? its a small power connector from the PSU usually with 4 or 8 pins apart from the big 20 pin connector which powers the motherboard... your symptom says cpu fans spin but pc wont boot... could mean that the mobo is powered but not the cpu...
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November 29, 2010 5:26:53 AM

i connected the 8pin and the 20+4pin and i believe i connected it thorougly
but that problem is not the only, the PSU makes my room loose power
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a b ) Power supply
November 29, 2010 7:19:22 AM

Please try changing the PSU; my guess its shorting...
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November 29, 2010 1:22:32 PM

If you let the computer sit for a while, does it start to boot at all?

If it doesn't then either your psu or mobo is bad. If you systems starts and then shuts off your cpu is too hot. If your system keeps restarted your mobo is bad.

Also, you may have a button hooked up incorrectly so you are actually switching the reset switch which simply causes a short surge of power. Just a thought.
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November 29, 2010 7:40:03 PM

i tried with another PSU and pc starts up smoothly
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a b ) Power supply
November 29, 2010 11:12:29 PM

then replace the psu
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November 30, 2010 1:01:14 PM

i sent it back to the hellhole it originated from now i will wait for a new one -.-
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