When I turn on the power supply, the LEDs on the MB lights up. Everything fine so far, but the fans (neither the CPU fan nor the chassis fan) won't spin. Nothing happens except for the LED lights on the MB.
Nothing happens on the screen. Not even a POST. No beeps.
I have checked all the wires, although no errs discovered so far. The 20-pin ATX connector is connected correctly, the other 4-pin ATX connector as well.
What is wrong here? Does the problem rely within the PSU? I have also tried to boot with the MB outside the chassis, albeit to no avail.
pull everything except the CPU and see if it beeps, if it does then try putting the SO-DIMM in it, see if it beeps, posts or anything.
Also do you have a basic PSU tester?? or another known running system you could hook the psu into to check it??
Youre saying its not even bumping the fans when you push the button??
Its possible you,ve plugged the switch in to the wrong pins also.
Alright so, I decided to check whether the PSU is dead or not. It turns out it is. I followed this guide and even then nothing happened to the PSU fan. Absolutely nothing. Hence, I am rather confident in concluding that the PSU is indeed dead. Or, should I say, not supplying enough power to power up the components (fans, CPU, GPU, SSD, etc), only the MB LEDs.
Now, onto something else. I sincerely hope the MB isn't dead as well. After all, can it really be? I mean, all LEDs are working perfectly. I switched the CPU core unlocker on the MB on, and accordingly, its adherent LED light turned on.
The MB can't be dead, right? This means, all this hassle is caused by the PSU (which is proven dead)?
Certainly sounds like a DOA power supply, an unfortunately common problem when buying a case that includes it. If you can afford to buy a replacement I would recomend that path.
Highly un-likely that the MB is bad...you never have enough power going to cause any harm!!
Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.
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: 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%. If you have a white wire (many modern PSU's do not), it should be -5 volts.
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.
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.