System starts up and shuts down repeatedly after PSU replacement

Hello All,
After changing our power supply in order to have enough power to add a GPU for Crossfire, the computer starts up to the single short "POST successful" beep and then the computer shuts down. It stays shut down for approximately 6 seconds and then starts again. This situation repeats continuously until we turn off the power switch on the PSU.

1.We have worked our way through the troubleshooting procedures posted here ("PERFORM THESE STEPS before posting about boot/no video problems!" ).

2. Tonight we pulled everything out of the case and breadboarded it according to the procedures listed here (http://www.tomshardware.co.uk/forum/page-262730_13_0.html). The cycling problem persists.

3. We re-connected the original power supply that was working previously and we had the same problem.

4. We got all of the proper beeps when we started it without memory but the computer shut down immediately after the continuous short beeps and cycled. The troubleshooting procedure didn't mention whether the computer should stay running after this test or if it shuts down but this leads us to believe that the motherboard and processor are working properly.

Our computer specs are as follows:

Motherboard: Gigabyte H55M-USB3
Processor: Intel i3-540
Processor heat sink is stock
Memory: 8GB (four sticks) ADATA AX3U1600GB2G9-2G DDR3 1600
New PSU: RaidMAX RX-630SS
Old PSU: Logisys 480W that came with the case.
Graphics Card: XFX Radeon HD 5770 1GB GDDR5

Could this be a temperature issue? Frankly, I am at the end of my knowledge here so any help would be greatly appreciated. I have a teenager going through gaming withdrawls. It is not pretty...

Unfortunately on the PSU front you traded bad for bad. Raidmax are OK for low end web surfing box, although I would not buy one even for that. Besides the poor general quality of Raidmax, they are never the wattage they claim. Your 620 is more like 500 at best, assuming you got one that actually works. If they fail, they will also take the rest of your system with them.

What you need is a quality 80 Plus certified or better from a trusted maker such as Corsair(not builder series), Antec, Seasonic, Silverstone, or XFX. Even a OCZ 600w ModXStream Pro would work for you. I did not include OCZ in the initial list because not all of their PSU's are that good. I can vouch for this one as I have it. It is also an excellent deal right now. It will be more than enough for your setup. http://www.newegg.com/Product/Prod [...] 6817341017

edit: Note the price after rebate. I had no trouble getting mine.

tlmck is correct about the overal quality of Raidmax PSU's.

I have expanded the procedures but have not added them to my original breadboard thread.

The following is an expansion of my troubleshooting tips in the breadboarding link in the "Cannot boot" thread.
http://www.tomshardware.com/forum/ [...] t-problems

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

Breadboard - that will help isolate any kind of case problem you might have.
http://www.tomshardware.com/forum/ [...] adboarding

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. At this point, if you do not have a system (internal case) speaker, you really need one.


Make sure you plug the CPU power cable in. The system will not boot without it.

I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

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

If no beeps, LED's, or fan activity:

Check for line power at the PSU input. Extension cords, power strips, and power cords do fail.

If you have power and no beeps, suspect components in likely order are PSU, motherboard, and CPU.

Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

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=5FW [...] tube_gdata

A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

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, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

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.
At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

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.

I actually found your expanded procedures elsewhere on the forum and we have followed them. I did not check the PSUs with a multimeter because, by swapping back in the known good PSU and still having the same problem, I decided that it was not necessary. Excellent troubleshooting procedure, btw. Thank you for posting it and maintaining it.

We haven't checked every stick or every port yet. I will try that tonight. From the procedures that JSC posted I don't think that is it but it is worth a try!

I jumped the green wire to a black one and all the fans started up fine, I am guessing the psu is good, that leaves the mother board or the processor how do I tell which one?