Computer Not Starting

Sorry I cannot give you any of the required info on my older desktop computer, it is a bitsa and not a brand name, has an Asus mother board, with I think an i5 chip, has both an SSD and a hard disk drive and also a replaced DVD drive, and I think it is about 11 years old.

The computer was working with no blue or black screens or any problem for that matter, I tried to turn it on a day later and it doesn't start at all, I have removed the 24 pin power pack connection and bridged pins 16/17 and the cooling fans runs as per test, -- with the side cover off and when I press the start button, the cooling fans will start to spin and then stop, there is a green LED on the mother board and this is constant green.

The unit has a 4 wire push button on/off switch, would it be ok to bridge the 2 start wires, or would this create a short, I am not familiar with computer switches, but ok with automotive, would there be a schematic of a 4 wire computer switch that I could have a look at?.

I am thinking the problem could be the switch, any other ideas someone may be able to help me with?.

Thank you in advance.

 

The usual power switch is just two wires to the motherboard jumpers (this is a generally speaking) and shorting them is what a switch actually does, that said I've never seen four wires.. like a double pole double throw switch? The case would usually have a normally open momentary switch to power on, or some older ones might have a latching switch (stay down when pressed, releases when pressed again).
Anyhow, with the specs you've described it sounds like this PC is not that old...
Grab the mobo manual from Asus and see what pins on the board are for the power button and briefly short them & see if it comes on.

1) Pull the power plug, push the power button, then plug it back in and hit the power button.
2) Unplug USB devices, keyboards, mice, leave only the monitor - repeat step one.
3) Open case and remove any cards, RAM, SATA/IDE from MOBO - so you have the front connectors, CPU , cooler, mobo power 24pin (any extra mobo power) and monitor connected - repeat step one.
If it is still dead, you can try a new power supply, remove all the remaining parts from the case and see if it boots on the table.

 

Thanks for your advise foogoo, I have a new 4 wire switch coming, the extra 2 wires are for the LED in the switch button, I had to ask the question though.
I can start pulling things as you suggest and do the tests.
As I mentioned, I removed the power supply 24 pin connector and bridged pins 16/17 as suggested and the power supply fan ran, it was said that if the fan runs during this test, the power supply is ok, what are your thoughts on this test foogoo?, I have asked this question for guidance.

This will be a slow process posing questions and answers on this forum, I have a near new Desk Top Computer that my grandson and I built some months ago, the older Desk Top has a lot of Data on it and I need to keep this running for awhile yet.

 

I mean shorting those pins and the fans startup is a slight test of the viability of that power supply, I've had power supplies that passed the 'test' until under load, then they fail.
You can get a power supply tester, usually under $20, before you buy a new power supply.

 

I removed the front panel yesterday and it seems like the original on/off switch is part of the panel, when the new switch arrives, I will have to drill a new mount hole for it, that is if I use or need to change it.
I have also bought a new power supply, this wont go astray if the original power supply hasn't failed, I will find this out when I get the new one and do a switch.

I will also look into the power supply tester you mentioned, it wouldn't be a burden to have on hand, seeing that there 7 desktops in our household.

I also pulled the CR2032 battery yesterday and this is reading 3.2volts.

 

I found the build invoice for the old desk top,
build date 9/01/2013
Had an i3 originally, I am sure I replaced this with an i5
Asus P8H61-M LE/USB3 LGA1155 MB
4gb Corsair DDR3 RAM module
550W ATX power supply
Gigabyte graphics card GV-N740D50C-2G1 REV:1.1
originally had a Samsung DVD drive, replaced that about 6 months ago, brand unknown.
Checked the battery again reads 2.9volts, I had the mains power turned off overnight.

 

The BIOS battery - that 2032 would not stop the PC from booting it would tell you the BIOS was reset the date, time and any other customizations in the BIOS would be back to default - like boot device, CPU/RAM clock settings, but you would still be in the BIOS, not a blank screen.

 

An update, have replaced the power supply and this made no difference to the starting of the computer, just get a flick from the CPU fan and the graphics card fan spins and then stops, which is the same as per the old power supply.
Have bought the same type motherboard and waiting for this to arrive, also still waiting for the start switch to arrive.

 

Yeah, I would lean toward MB failure. It may have already been mentioned, but unplug everything from the MB, HD's, video card, (use onboard for test), all usb devices. Leave only one stick of ram installed. Short power pins on MB and see what happens. If it powers up, turn off and start replacing one thing at a time until you see what is causing it to not start.

 

For your info too foogoo!!.

The PSU testing unit arrived a couple of days ago and the old power supply tested OK, the on/off switch arrived yesterday and I plugged this onto the board and this makes no difference, I have removed the ram from the board as previously suggested, what do you class as USB devices?, wireless dongles, WIFI antenna?.

Hopefully the replacement MB will arrive by the end of this week or early next week.

There would have to be an electronic on/off switch on the MB controlled by the on/off switch on the front of the computer tower?.

I had a thought yesterday, if the CPU went crook, the computer would fire up sort of ???, or do what is happening now??.

 

You will need at least one stick of ram installed for it to boot.

Yes it appears not to be the PSU.

I was stating unplug ALL components. Any one of them could cause a no boot issue if bad.

If CPU is bad, that too will cause a no boot. If you have a second known working CPU that will work with MB try it to rule out bad CPU.

If you have a good known working stick of ram, use it. If you only have one stick of ram, you can not rule out a bad stick of ram. It too can cause a no boot.

A USB device can be anything plugged in through USB.

I typically exhaust all test that cost nothing first, then test with new or know working used parts. I know that is difficult for someone that does not have a large cache of parts like I do, as I repair PC's.

Hope you figure it out soon, good luck sir.

 

Thank you and a good day to you.

 

What do I classify as USB? anything you plug into a USB port - you want power, cpu & motherboard - that is it... no RAM you want it to beep and say there is no RAM a slight proof of life. You really should remove all the "front pin connectors" power switch, reset, LEDs...and just short (very carefully) the power pins to see if it boots. If you don't want to give up there remove the system from the case and see if it will boot, after that call a priest..

 

Motherboard arrived Thursday, later today I will start to strip out the original MB, I will have to get my grandson to swap over the CPU because I have Carpal Syndrome in both hands and the fingers have no feel to hold, I don't want to bend the pins on the CPU trying to refit.

I will fit the Motherboard and power supply and power up before refitting the rest of the hardware, I will give an update if all goes well.

 

Yesterday, Saturday, my grandson removed and refitted the CPU into the replacement MoBO and all the associated power and data harnesses, switched on and basically we got 2 short beeps with the computer firing up and then shutting off, this was repeating itself until we shut power off at the switch, this morning I started disconnecting hardware, removed the graphics card, disconnected the SSD and hard drive and finally the "DVD recorder/player", doing that fixed the stop/start problem and may well have been the problem all along, I am bending over waiting for the kick in the derriere, go for it!!.

I do have another problem now, I use a smart TV screen (about 2 mths old) and I am getting the message, no data, I have used a HDMI (new) cable between graphics card and the TV screen with no previous problems, seems like I am not done yet with this dinosaur.

 

Two short beeps from an ASUS computer indicate a base memory error.
Plugged in the right place? Is there onboard video? using a video card?
TV on the 'correct' hdmi port?

 

With reference to post #15, when I connect the DVD Rom to MoBo and PSU and then turn power on, is when I get the two short beeps, disconnect the data cable and power supply from the drive and the beeps are gone, which to me at this time is not important.

The PSU is a new 700w unit and I hooked up the digital tester which I think read ok ( no instruction info), so that can be bypassed.

I am not getting a signal to the TV screen no matter what position I set the TV screen to using the HDMI cable, even connecting to the HDMI connection on the MoBo doesn't help, I have also used a 15 pin AVG cable attached to the video card to the TV, and from the MoBo to TV, and still no signal.

I had thought of buying a cheap video card to see if that would help, but I believe that I would be throwing money at a wall, the fact that I am not getting a signal from either the video card or the MoBo, could this indicate that maybe the CPU has had it?, The fact I connected an AVG cable from MoBo to the TV and set this to PC on the settings and get a "no signal" info box, the TV screen is only a couple of months old and I can bring up menus and the like with no problems, it will run through setting up TV channels, but with no antenna, wont find any.

The second hand MoBo I bought has warranty and came from China, I don't think it would be a dud, but anything is possible.

I would have thought there should be beep codes if there is a problem with the CPU, MoBo, Vid card or memory.

What do you blokes think??.

 

I went onto ebay Au., and came across a MoBO with an i5, 32 gigs ram and a cooling fan, starting at $10Au., so I may keep playing a little longer, sent the seller asking if the CPU works, so the waiting game starts again.

 

ASUS, supposedly 2 short beeps are RAM, so did you install the RAM? Kinda jumping ahead hooking up a DVD.
The test should be mobo, CPU /cooler fan & power supply - Beep = possible life - Google Code? RAM? add RAM, boot again? Beeps? Google Beep. One beep-
display plugged in - video? POST (beep)? Yes, continue adding parts back in..add something back in and Beep stops, remove and install the next part...
wash and repeat.

 

Foogoo, I did what you suggested earlier in the post, removed Graphics card, removed 1 ram and then swapped for the other ram, removed the connections to the hard drive, then the SSD drive and finally the DVD Rom drive, and each time would shut the computer down and then reboot, the 2 beeps stayed there until I removed the power and data cables to the DVD Rom and on reboot, the beeps were gone, the only parts replaced back in the slots were the 2 sticks of ram, -- the graphics card and the drives were left disconnected while testing.

With the Graphics card, HD and SSD connected, -- the DVD Rom disconnected -- when rebooting I get the typical short drawn out beep on start, no other beeps.

And as I wrote in post 17, using either the HDMI cable or the 15 pin AVG cable, I am not getting a signal to the screen, this "no signal" is displayed on screen, I have a DV1 cable, but the screen doesn't have the receptacle for the connector.

I am sorry for dragging this out, I really thought the PSU would have fixed the problem,