Computer Boot Problem

PleaseHelpJames

Commendable
Jun 2, 2016
7
0
1,510
Hello all,
My friend and I have created this computer a few months ago and it was working perfectly. Around a few weeks after the building of the PC, the problem started but I just waved it off and now that I have realised it's still consistent I've decided to seek out for help. I've been looking for solutions all over the place and most of them sent me to the POST check link and I ran through it all to no avail. I checked out other "SOLVED" threads and tried to follow the answers to similar problems but still nothing came up to be the solution. I moved the RAM to the other slot, unchecked fast-boot up etc. I also had the PSU replaced but the same issue consists.

The problem is with the boot up of the PC itself. I wake up to turn on the computer, everything is working, I can hear the fans moving etc but there is no output. I then press the restart button on the case, it reboots and then I get output and the computer works fine. If i shutdown my computer there is no issue turning it back on but if the computer stays off for about over 1 hour or I turn the power off from the back, the no output problem comes back.

I opened up the computer to see what the problem was, I made sure the the 8pin 12v was connected as well as the 24pin connector. My PSU is CX750M — 750 Watt 80 PLUS (It's semi-modular so the cables that come straight out of the PSU go directly to the right place. I put the CPU cable coming out of the PSU into it's correct place for example.)

Components:
PSU: CX750M — 750 Watt 80 PLUS
CPU: Intel Core i7 i7-4790K
GPU: MSI GTX 980TI

Thanks in advance and hopefully someone comes up with the correct solution. This problem is really annoying and I am pretty worried that it might start affecting the hardware.
- I already looked at 12v 2.2, 12v 2.3 and I saw that my PSU is 2.3 unless that's wrong. This dude explains it and I thought the issue lied there but maybe i'm wrong. https://www.youtube.com/watch?v=_yiNEZWpLZ0
 
Solution
If it turns out the RAM is the issue, then that module is bad and needs to be replaced. What I'm thinking the issue is one of the modules is bad, so when the PC shuts off, it's not dumping data properly. But your further testing will prove or disprove this.

thejackal85

Reputable
Jan 18, 2016
1,181
0
5,960
It sounds like some of the hardware may already be malfunctioning. Booting issues like this can be caused by a few things: CPU, RAM, or other PCI related devices. So here's what I would do.

1. Test with the RAM modules. Remove some, put them in different spots and test booting and performance.
2. Reseat the processor and make sure its not overheating (BIOS should tell you this).
3. Reseat your GPU (into another slot if you have one).

Let me know how this turns out.
 

PleaseHelpJames

Commendable
Jun 2, 2016
7
0
1,510
@thejackal85
Hey thanks for the reply. So I tried the 3 options and nothing. I swapped the spots for the RAM modules, like i said above but this time i just tried to boot with only one. The system booted up fine but that's probably because the computer hasn't been off for a while. I then removed the cpu fan, lifted cpu, reseated, applied new thermal paste and put the cpu fan back on. Still the same thing. I'm not sure if anythings changed so far because the computer hasn't been off for a some time. I reseated the GPU but not into another slot because of space issues. I'm going to keep the computer off for an hour or two then try boot with one RAM module and i'll see.
Thanks for the help.
 

PleaseHelpJames

Commendable
Jun 2, 2016
7
0
1,510
@thejackal85 No power issues ever. I'll post pictures of my power supply cables and where i've plugged them in. Thanks for the help man, it's really appreciated. Please wait till when I can post pics. Thanks in advance.
 

PleaseHelpJames

Commendable
Jun 2, 2016
7
0
1,510
@thejackal85 So i kept the computer off for around 6hours+, this should bring the problem back if i were to power the computer up. Before i turned it on, i removed a RAM module and it booted up without any issues. I'm going to try this after waking up and hopefully that is the cause because i've been looking for a solution for some time now. If the RAM is the issue, what should i do?
 

thejackal85

Reputable
Jan 18, 2016
1,181
0
5,960
If it turns out the RAM is the issue, then that module is bad and needs to be replaced. What I'm thinking the issue is one of the modules is bad, so when the PC shuts off, it's not dumping data properly. But your further testing will prove or disprove this.
 
Solution

Paperdoc

Polypheme
Ambassador
I'll suggest a different possibility to check. What I notice in your post is that the problem ONLY happens when power has been off for a long time. You can reboot when it is running, and you can even shut down and do a cold re-start successfully as long as the shut-down is under an hour or so. This does not sound very much like a faulty major component.

I suspect that the BIOS battery is weak. That is the silver disk (about the size of a quarter) mounted in a holder on the mobo. When the computer is running the voltage needed by the BIOS's small RAM chip is supplied from the PSU, but when the machine is shut down that power must come from that little disk battery. If that battery is weak it may do the job for a limited time, but eventually it will fail and that special RAM will lose its data. I'm pretty sure that, if the BIOS detects on the next start-up that its RAM has no data, it automatically copies a set of "factory default" data from its PROM into that RAM space and uses that to boot. However, doing that takes time and may leave the BIOS in an unstable state. BUT once that has been done, the RAM does have the data, and a reboot immediately does not have this problem.

You could test that battery, or just buy a replacement and put it in, to see if that solves the problem.