I came home from work today and found that my (home) computer had frozen, so I turned it off and then turned it back on.
...And nothing happened. It powered on, but no POST, no beeps, and just a blank screen with nothing happening. Turned it off again, turned it back on, nothing. Tried it a third time, it went to POST, saw the bios, didn't react quickly enough to hit delete and then the screen went blank. Haven't had any luck since then--powers on, but no POST, no beeps, and just a blank screen.
I removed components from the computer one-by-one, but no luck--still no beeps or anything else. Finally just had the PSU supplying the motherboard and the CPU, and I did get the beep pattern indicating that I had no memory in.
I have two sticks of DDR3 RAM--tried just one module and then just the other module, and tried different DIMM slots on the motherboard, but no luck.
The computer is only a year old custom-build and has been operating perfectly. That said, yesterday, I did bump my desk hard enough that the computer froze. When I restarted everything was working fine and I used it for the rest of the night with no problems at all. So, I'm thinking this was just a coincidence, but who knows...
I've also tried resetting my CMOS, via the jumper and via removing the battery, but no luck there, either.
Any ideas of what I should do? Or what is wrong?
Right now, I'm thinking of either ordering new RAM, and hoping that is what's wrong with it, or taking it to a computer repair shop (first time I'll have ever had to do that, if I do ).
Any help/suggestions/ideas would be much appreciated!
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%.
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.
Well, I did all this, and I have my motherboard out of the case on a piece of cardboard, with just the CPU and HSF plugged in, and when I start it up, I get the diagnostic beeps that the RAM is missing. When I put the RAM in, I get silence.
So, I guess that means that my RAM (both sticks), after working for about a year, just decided to up an' die?
P.S. I also tried an older, but known good PSU--no luck.
I had a SAPPHIRE Radeon HD 5770 1GB video card in it, and it was the part of the PSU that supplies the video card and the PCIe slot that it was in on the motherboard that both burned out--you don't think this wasn't a strong enough PSU, do you?
EDIT: funny thing though, that the video card is apparently fine.