Question no signal to both monitors tried many things not sure whats wrong with my pc

[BHTrix]

Hello everyone!

I’m running into a problem of which I wouldn’t know how to diagnose what the problem is.

I went for a nap and when I woke up my computer was running but my screens where black.

I forced a reboot but my screens remained black (it says no signal on the screens)

I’m relatively confident it isn’t both my screens that died at the same time (I even tried a 3rd screen)

my cpu does not have integrated graphics.

I have a radeon challenger rx 5700 for a videocard.

I have tried different (but very old) videocards. a radeon r580 and a xfx 7800 (these still have dvi ports heh) they give black screens as well. But then I’m not 100% sure these old cards still work.

I have tried a different pci slot, with no success.

The thing that’s weird to me is that, I would expect the computer to boot up to windows login screen, even if the monitor doesn’t work

but i hear no sounds (windows 11) and I’m kind of thinking that I should hear sounds when I for instance type in the wrong password and hit enter.

Anyone got some ideas or resources I could check out?

tx in advance

Paul

 

[LinuxDevice]

It is hard to say for sure, but it is possible the power supply failed.

Do you have anything else you can try the monitors on? If you have a router with admin access, and another computer, then you could check the DHCP logs to see if an address was requested (which would indicate it is booting, but the display is failing; different than if no DHCP is requested).

Short of trying the monitor(s) on another computer, I think I would try a power supply next (it would have to be of sufficient power output to support your hardware). If you were to take your computer to a local shop, then they might be willing to put a power supply tester on it in hopes that you would use them for service or purchase a supply.

 

[BHTrix]

It is hard to say for sure, but it is possible the power supply failed.

Do you have anything else you can try the monitors on? If you have a router with admin access, and another computer, then you could check the DHCP logs to see if an address was requested (which would indicate it is booting, but the display is failing; different than if no DHCP is requested).

Short of trying the monitor(s) on another computer, I think I would try a power supply next (it would have to be of sufficient power output to support your hardware). If you were to take your computer to a local shop, then they might be willing to put a power supply tester on it in hopes that you would use them for service or purchase a supply.

tx!

i will check this out

i have a macbook, and ordered a usb-c to display port adapter, so i can check the monitors on monday

unfortunately i can’t seem to find my old power supply. I’m relatively confident i have lifetime warranty on this one though

evga supernova 750 if i remember correctly

 

[BHTrix]

It is hard to say for sure, but it is possible the power supply failed.

Do you have anything else you can try the monitors on? If you have a router with admin access, and another computer, then you could check the DHCP logs to see if an address was requested (which would indicate it is booting, but the display is failing; different than if no DHCP is requested).

Short of trying the monitor(s) on another computer, I think I would try a power supply next (it would have to be of sufficient power output to support your hardware). If you were to take your computer to a local shop, then they might be willing to put a power supply tester on it in hopes that you would use them for service or purchase a supply.

another question, just because i would like to understand how it can be the psu

cpu fan is working, all the lights are on, and even the fans of the gpus work

albeit strangely enough of one of the older gpus one of two fans worked but that could be because it’s just a very old and maybe broken card

is this not evidence enough that the psu is working?

i am looking at psu testers, they are like 15 euro so i might actually just order one and hopefully get it on monday

 

[BHTrix]

ok, i have absolutely no idea why, but my computer has screens again, and i have logged in. i would still pretty much like an idea of what has happened though

heh

any ideas would be great
and perhaps there are ways to see what has happened? diagnostics or something?

 

[LinuxDevice]

FYI, computer power supplies have many power supplies within them. There is a +3.3V rail, an +5V rail, and +12V rail, and a -12V rail. Each rail can fail independently of the other. That means fans and other parts might still work even when the logic is gone ("the lights are on, but nobody is home" 😱).

Also, quite often a PSU will have multiple ports/cables at a given voltage, e.g., +5V, and several might go to one +5V supply, but others might be a separate +5V source. Combining two from the same source implies you didn't do anything to increase available current, but combining two from separate rails makes more current available; hook up the wrong two and the supply is overloaded, hook up the correct two, and it works (this is unlikely to be the case for your situation, I just mention it because I want to illustrate that computer PSUs are a lot of little pieces and it matters how you combine them when you are looking at a failure case).

You can actually get a power supply tester, but this implies unplugging all of the cables and putting them on the tester. This might also not tell you about cases where you're just consuming too much power for that PSU rail. Video tends to require a couple of plug-ins to the extra power connectors on the GPU card, plus the power rails delivering current through the PCIe slot. If all of the power is not correct, then the GPU won't function (and often the fan on the GPU does still function). Power issues on GPUs are quite common.

 

[BHTrix]

FYI, computer power supplies have many power supplies within them. There is a +3.3V rail, an +5V rail, and +12V rail, and a -12V rail. Each rail can fail independently of the other. That means fans and other parts might still work even when the logic is gone ("the lights are on, but nobody is home" 😱).

Also, quite often a PSU will have multiple ports/cables at a given voltage, e.g., +5V, and several might go to one +5V supply, but others might be a separate +5V source. Combining two from the same source implies you didn't do anything to increase available current, but combining two from separate rails makes more current available; hook up the wrong two and the supply is overloaded, hook up the correct two, and it works (this is unlikely to be the case for your situation, I just mention it because I want to illustrate that computer PSUs are a lot of little pieces and it matters how you combine them when you are looking at a failure case).

You can actually get a power supply tester, but this implies unplugging all of the cables and putting them on the tester. This might also not tell you about cases where you're just consuming too much power for that PSU rail. Video tends to require a couple of plug-ins to the extra power connectors on the GPU card, plus the power rails delivering current through the PCIe slot. If all of the power is not correct, then the GPU won't function (and often the fan on the GPU does still function). Power issues on GPUs are quite common.

tx! that was mega informative and very good to know

thanks for taking the time to type that out!