PC shutdown itself, help

My pc shutdown itself some times because this goes so far i finaly want to ask for help, sometimes when pc shutdown i check eventviewer at system logs and i found some errors critical, kernel power, pc shutdown was unexpectedly etc. i dont know what this exactly mean but i need help, maybe because in device manager i have unknown device under usb ports this shows everytime even reinstalling pc cant fix can this cause the problem
And today shutdown after 5 seconds when i turn on pc
Any help would be nice thanks

all stop working and i cant find the led on motherboard with green light i have never seen that led on

Nenad2 said:

pc shutdown was unexpectedly
i dont know what this exactly mean

Neither does Windows. If you check the timestamp of that error message, you will likely see it was made when you rebooted, not when it shut down. It just means Windows detected it was not shutdown properly.

It is common for no errors when a computer suddenly shuts down because the shutdown occurs so quickly, Windows has no advance notice to write any errors.

TVeblen said:

I can't remember back to when they did not have the LED.

Most don't! There is no, and never has been any standard requirement for motherboard LEDs. And the fact is, the vast majority of motherboards today don't have any LED status indicators. That is an extra, optional feature as they serve no purpose for most users who can't see them anyway inside a closed case.

And for those motherboards that do, there is no standard color, no standard for the number of LEDs, and no standard for what a lit, or unlit LED means. The most basic simply indicates the PSU is delivering the ATX required +5Vsb voltage as a reminder to unplug from the wall before removing or inserting RAM. More advanced (read: expensive) motherboards may have several LED indicators that show boot progression status. But even many high-end boards don't have any LED indicator lights.

So again, most motherboards sold (today, or ever) have LED indicator lights. You would have to look at the specific motherboard's specs to see if this board does, or not, and what it means if lit.

@Nenad2 - If me, the first thing I would do is swap in a known good power supply. Everything in your computer depends on good, clean stable power. Then I would test the RAM, either by pulling all but one stick and running with that for awhile to see what happens, and swapping in sticks to hopefully find one that is bad, or by running MemTest86 for several passes. You should have "no" errors. Windows 7 and Windows 8 users can use the built in Windows Memory Diagnostics Tool.

TVeblen said:

How old is this motherboard? I can't remember back to when they did not have the LED.

Probably best to post your system specs. You do that in your forum profile. Fill everything in the best you can.

Sorry for late reply, well i dont know this pc is brought 3-4 years ago motherboard is gigabyte ga-m52l-s3

sometime working fine well till i started thread didnt shutdown now its fine but sometimes in random moments shutdown it`s happening so rarely

Itaregid said:

Nenad2 said:

pc shutdown was unexpectedly
i dont know what this exactly mean

Neither does Windows. If you check the timestamp of that error message, you will likely see it was made when you rebooted, not when it shut down. It just means Windows detected it was not shutdown properly.

It is common for no errors when a computer suddenly shuts down because the shutdown occurs so quickly, Windows has no advance notice to write any errors.

TVeblen said:

I can't remember back to when they did not have the LED.

Most don't! There is no, and never has been any standard requirement for motherboard LEDs. And the fact is, the vast majority of motherboards today don't have any LED status indicators. That is an extra, optional feature as they serve no purpose for most users who can't see them anyway inside a closed case.

And for those motherboards that do, there is no standard color, no standard for the number of LEDs, and no standard for what a lit, or unlit LED means. The most basic simply indicates the PSU is delivering the ATX required +5Vsb voltage as a reminder to unplug from the wall before removing or inserting RAM. More advanced (read: expensive) motherboards may have several LED indicators that show boot progression status. But even many high-end boards don't have any LED indicator lights.

So again, most motherboards sold (today, or ever) have LED indicator lights. You would have to look at the specific motherboard's specs to see if this board does, or not, and what it means if lit.

@Nenad2 - If me, the first thing I would do is swap in a known good power supply. Everything in your computer depends on good, clean stable power. Then I would test the RAM, either by pulling all but one stick and running with that for awhile to see what happens, and swapping in sticks to hopefully find one that is bad, or by running MemTest86 for several passes. You should have "no" errors. Windows 7 and Windows 8 users can use the built in Windows Memory Diagnostics Tool.

Well i tested memory 2-3 this 2 month didnt find any errors model of PSU is ATX-400W P4
PC is 2 gb ram i have pc spec in profile if this can help for now its fine pc didnt shutdown till i started the thread shutdowns are happening so rarely at random moments, my main question is because i have some usb port who isnt recognized in device manager and do that failed hardware can cause pc to shutdown?

TVeblen said:

If your motherboard had a low power indicator LED we would know if ALL power was going out when this happens.

Sorry, but no, that is not true either. The PSU outputs 3 separate voltages used by the various computer components; +3.3VDC, +5VDC, and +12VDC (plus +5Vsb standby voltage for when the computer is in sleep and standby modes). One "low power" LED indicator (and I have never seen a "low" power LED so sure would like to see a link to such a motherboard) could not report statuses of all 3 voltages.

As I noted above, typically, IF the motherboard has "a" LED, as in 1 LED, it is there to remind users there is still power present on the motherboard, such as when the PSU is outputting the ATX Form Factor standard required +5Vsb standby voltage needed for the various "Wake on..." commands - such as "Wake on Mouse" and "Wake on Keyboard", as well as the case's front panel power button.

But again, most motherboard's don't have power indicators because the case's front panel power LED indicator tells you when your computer is on (LED solid), S1 Sleep state (LED flashing), or S3/S4 sleep or powered off (LED off).

It is important as helpers we research the OP's computer specs and not assume what we see on our computers is the same with everyone's, so we don't confuse and lead readers astray with time wasting misinformation. A quick look at the GA-M52L-S3 User's Manual confirms this Gigabyte board does NOT have any motherboard LEDs, except for the Activity and Speed LEDs for the integrated NIC.

Personally, I don't see this being a faulty CPU since it does work sometime, unless the CPU is overheating. Are the case interior, CPU heatsink and vents all clean of heat-trapping dust?

Nenad2 said:

Well i tested memory 2-3 this 2 month didnt find any errors model of PSU is ATX-400W P4

Did you let the RAM tester run for several passes? That is important but note no software based memory tester is conclusive. If they report errors, the RAM is bad. But they often report no problems but the RAM still fails when installed, or when paired with other RAM. So testing and/or running with one stick at a time is often necessary (or simply swapping in new RAM).

As for your PSU, "ATX-400W P4" is a "generic" designation. So as I mentioned above, swapping in a known good supply to ensure good, clean power is the first thing I would do. Without knowing for certain the PSU is good, you cannot be certain problems seen with other components are not due to bad power from the PSU.