Hi all, thanks in advance. I am building a pc, and can't get it to the POST. After pressing the 'on' button, I get power and hdd led's lighing up, case fans and video card fans spinning, but the cpu fan is silent and I get no video output. There's no audible beeps with or without the RAM, which are both in the red slots, like the manual suggests.
The motherboard has power input options for both mobo (20 or 24) and cpu (4 or 8) power. I've tried all 4 combinations and still no change.
I just purchased the following:
OCZ Modxtream-pro 500W
Intel i5 2500k
2x4GB Patriot DDR3 1600MHz Ram
ASRock P67 (Fatality)
XFX Radeon HD 6770
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:
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.
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.
Also, have you tried switching out sticks of RAM? As in, leaving one stick in at a time?
It's very common that a PC will turn on without beeps and output no video when one of the two sticks of RAM is bad. So try putting one in, leaving the other out, and see what happens. If it's the same result, do the same with the stick that was left out, and leave the one that was in out.
I had this exact problem with my new build. Hit the power button or short the jumpers and CPU fans spins up for a couple seconds before all does dead - and no beeps at any point, no post to be seen anywhere.
I was breadboarding anyway so I performed the build equivalent of a turn it off and turn it on again - I took EVERYTHING apart. Right back to removing the CPU.
And what did I find? The CPU had somehow become unseated during the installation of the HSF.
I have zero idea how I managed that (possibly as it's a FM2 slot it didn't lock properly) but I did, and this was the cause of the no beeps, no post but all other components working fine.
Solution was to punch myself in the face for my stupidity and sausage fingers, reseat the CPU, rebuild and enjoy a working computer.
Might be worth a quick check for any others stumbling on this post in frustration at the standard procedures not giving a clear solution.