PC monitor won't turn on

[westside]

One PC desktop is connected to the PC input of the HDTV and all of a sudden came on then literally fizzled out slowly as I was booting up after I got the desktop screen for a few seconds. The monitor is fine as it worked for another desktop. Monitor when plugged in to the 'bad' PC shows "In Power Save Mode".

So, I read online that the motherboard battery could be the cause and needs replacement. Other ideas were to reseat the memory. After popping out the battery, unplugging/replugging the power supply on the MOBO, and reseating the memory sticks, now the PC won't even turn on with the power button - but only when plugged in, the CPU fan just keeps spinning. Situation got even worse it seems.

I had another older PC desktop which I had not used in about 2 years, sitting in the closet. So, plugged that into the monitor and that too does not show anything on the monitor - but the same "Monitor is Power Save Mode" - so does PC#2 also have a MOBO battery issue? I don't want to pop out the batter, reseat, or unplug anything on PC#2 fearing the situation will become worse as with PC#1

- this may belong in the "hardware" subforum but since it began with the monitor I thought this may be the place

 

[MindoverMaster]

The BIOS battery has nothing to do with this. It is either your PSU not supplying enough power to your graphic card, or the graphic card is on its way out.

You didn't say, but did you put the battery back in?

 

[joelm3103]

I'll agree with MoM with his suggestions.

As for PC2, have you tried using a normal monitor with a VGA output (assuming you have a VGA output on your system) in which you can check if your PC needs to be manually selected to use the HDMI output.

 

[westside]

thanks guys for the help, both PCs are old (PC1 is 4-5yo dual core Companq; PC2 is 10-12yo Compaq - was literally in my closet) and only have MOBO video port - no HDMI, DVI or videocard

so I magically got PC#2 working (10yo Compaq single CPU - old and very slow) - even though I took the good PSU from PC#3 (good Dell PC) and it did not work in PC#2, but then put its own PSU back, thinking all was lost and by luck it turned on.

PC#1 - the 5yo dual core Compaq still won't turn on the monitor even though I swapped PSU with PC#3 (good Dell) and even its (PC#1) power supply worked on PC#3, so we know the power supply is not the issue, neither is the monitor itself.

weird thing is that PC#1 turns on when the power cord is plugged in (power supply in back shows green light) and then turns off by the front power button . But does not turn on again with the front power butten and has to have the power cord unplugged and plugged in - then the front power button - to again turn on. Sometimes the cpu fans also goes into hyperspin. I have a device to extract data from a removed hard drive but that is a time consuming process. Also tried the good MOBO battery from PC#2 (good Compaq) into PC#1 (bad compaq) but no luck. The keyboard does give the 3 green lights when the unit is powered on - so power is reaching some peripherals I suppose.

Is the MOBO dead?

 

[joelm3103]

One PC desktop is connected to the PC input of the HDTV...

This is why I thought you may have the HDMI output and maybe wasn't selected or a problem occurred which switched the outputs.

thanks guys for the help, both PCs are old (PC1 is 4-5yo dual core Companq; PC2 is 10-12yo Compaq - was literally in my closet) and only have MOBO video port - no HDMI, DVI or videocard

so I magically got PC#2 working (10yo Compaq single CPU - old and very slow) - even though I took the good PSU from PC#3 (good Dell PC) and it did not work in PC#2, but then put its own PSU back, thinking all was lost and by luck it turned on.

PC#1 - the 5yo dual core Compaq still won't turn on the monitor even though I swapped PSU with PC#3 (good Dell) and even its (PC#1) power supply worked on PC#3, so we know the power supply is not the issue, neither is the monitor itself.

weird thing is that PC#1 turns on when the power cord is plugged in (power supply in back shows green light) and then turns off by the front power button . But does not turn on again with the front power butten and has to have the power cord unplugged and plugged in - then the front power button - to again turn on. Sometimes the cpu fans also goes into hyperspin. I have a device to extract data from a removed hard drive but that is a time consuming process. Also tried the good MOBO battery from PC#2 (good Compaq) into PC#1 (bad compaq) but no luck. The keyboard does give the 3 green lights when the unit is powered on - so power is reaching some peripherals I suppose.

Is the MOBO dead?

Grats that PC#2 worked, guessing the PSU needed to be rechecked as you did take it out and put it back in. The Dell PSU didn't work maybe because it's proprietary.

PC#1 mobo could be dead since you tested more than 1 PSUs and no fix. Is there any beeps? When you stated it turns on, does it turn on and goes into Windows and stuff or just turns on temp then shuts off on you?