Question GPU Not Detected

Jun 30, 2021
4
1
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I got up to get some water the other night and came back to a black screen and no power to my computer. There was a faint smell of burning plastic and no response or power at all. I figured the PSU died on me. So I purchased a new PSU to start, just to see what problems there is. The computer boots without issues and I can hear Windows start, but there is no signal from the GPU and it doesn't seem like the GPU was even powering on. I swapped PCI slots and still nothing. I swapped GPUs and still nothing. So I plugged my monitor up to my Motherboard so I could have a look around Windows and BIOS and my GPU isn't detected at all, no matter what I do. Could it be possible that some how both my PCIe x16 and x8 are bad? I don't have a spare Motherboard to test out currently.
 
Hi,
  1. Are we positive the monitor is working?
  2. Have you tried to remove the cmos battery and leave it out for 5 mins or soo?
  3. Have you tried to unplug the PC from the wall and then pressing the power button many times for 1 min to let all static discharge?
  4. Have you tried 2 and 3 togheter?
  5. According to your specs, theres no RAM on the PC¨. Since we all know its not posible to start Windows without RAM, whats your current configuration?
 
Make sure you connected the auxiliary power cables back to the graphics card.

Make sure you connected your display cable to the graphics card and not the motherboard video outputs, speaking of which, have you tried using the integrated graphics from the motherboard (Need to remove the graphics card most likely for this to work)?

If that is all good, then try putting it back in the x16 slot and doing a hard reset.

BIOS Hard Reset procedure

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for about three to five minutes. In some cases it may be necessary to remove the graphics card to access the CMOS battery.

During that five minutes while the CMOS battery is out of the motherboard, press the power button on the case, continuously, for 15-30 seconds, in order to deplete any residual charge that might be present in the CMOS circuit. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

If you had to remove the graphics card you can now reinstall it, but remember to reconnect your power cables if there were any attached to it as well as your display cable.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP, A-XMP or D.O.C.P profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.

In some cases it may be necessary when you go into the BIOS after a reset, to load the Optimal default or Default values and then save settings, to actually get the hardware tables to reset in the boot manager.

It is probably also worth mentioning that for anything that might require an attempt to DO a hard reset in the first place, IF the problem is related to a lack of video signal, it is a GOOD IDEA to try a different type of display as many systems will not work properly for some reason with displayport configurations. It is worth trying HDMI if you are having no display or lack of visual ability to enter the BIOS, or no signal messages.

Trying a different monitor as well, if possible, is also a good idea if there is a lack of display. It happens.
 
Jun 30, 2021
4
1
15
Windows 10 64 bit and 16 GB DDR4 RAM if needed. I tried removing the CMOS battery to no avail. Yes my monitor works. I am using it now plugged directly in to the mobo on board graphics. I have re done the PSU and cables countless times. GPU is seated firmly. PSU cables plugged in firmly. The previous GPU I used was fine til what seemed like the PSU died. Left that GPU as it was and just installed a new PSU and no signal from it nor any other GPU I have tried.

It just feels like the old PSU going out on me caused some issues with the MOBO some how. The old PSU wouldn't power my computer at all, not even a little attempt to. If I flipped the PSU switch off and then back on I would get a quick flash from the CPU LED on the MOBO but that is it. New PSU installed and the computer booted fine and it even detects the CPU and RAM without issues so I don't know what else it could be other than the MOBO.
 
Did you buy that CX750m new or used, assuming that is the PSU currently in use?

If you bought it new, then it's very likely the old PSU took something out when it went. This is exactly why we recommend only buying quality power supplies that have full protections, but even then, if the PSU is very old it's possible to see the protections fail.

What was the model of the old PSU?
 
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Jun 30, 2021
4
1
15
I got a new MOBO and the GPU came right on. So oddly enough, the PCI slots went bad when my old PSU died on me. The old PSU was quite old. Maybe 8+ years old. A Corsair CX600M to be exact.
 
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Yes, the CX600 and CX600m are both known to cause damage to other hardware when they fail. We've seen more than a few cases of this happening with those specific models. They really were not particularly good power supplies. In fact, one of our moderators a few years back had a CX600 that died and completely toasted an almost new motherboard. So it's not too surprising.
 
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