Laptope restarting randomly (I've done a lot of tests, please read the thread)


Dec 8, 2016
Okey, so a while ago. My Laptop started overheating a lot (I bought it around mid 2012).

Laptop model is Toshiba L750-1N3.

Operating system: Windows 10
Processor: Intel Core I7-2670QM CPU @ 2.20 GHZ (Turbo @ 3.20 GHZ)
Ram: 8 GB Kingston DDR3 1866 (RAM has a higher freq then the stock one - but it is down clocked by the motherboard to appropriate speed. Worked for 4 years without a glitch)
Graphic Card: nVidia 525 2GB vRAM (+2 GB of RAM if I have 8 GB of RAM)
Driver status: Everything is up to date.
Battery is removed from the start (when I purchased the laptop I removed it).
Mouse: Logitech G502
Headphones: Logitech G633
Speakers: Some basic MS speakers
Keyboard: Lenovo LXH-EKB-10YA
Second monitor (via HDMI): Samsung SyncMaster 2232bw

- Laptop is behind an APC Power Surge protection unit.

First of all, the laptop had really bad temperatures all of a sudden. It went from 80*C to 100*C when playing games.

Details about the rig:
I have a Cooler Master cooler pad, with one additional fan built in (by me) from an old graphics card (right below the where the graphic card is placed on the laptop). The smaller fan and the cooler pad are on separate power. I used a defunct mobile charger and some super glue to make the fan work on a power socket. (Its a non issue, but I didn't want someone potentially pointing it out as a problem. It has worked for 2 years without any glitches. Problems started when the PC started overheating).

Onto the problem:

Laptop is primarily used for work and playing games (when not working maybe 5 hours a day - max).

But most of all, the Laptop is used for for work, I am a developer.

The laptop is on a lot, sometimes days at a time. (I have to leave the server up for Clients - when checking out beta versions of the apps/websites, different time zones etc.)

When the problem started with the restarts, I figured that it was probably the temperatures that caused the problem. After a few days with the high temperatures, I decided to go and buy a new thermal paste.

I've assembled PCs for the past 15 years. I've changed capacitors at the University so I am well versed how everything works. But this problem - I don't know whats happening.

I opened up my laptop, unscrewed everything and the thermal paste was worn down.

I cleaned it with is-propyl alcohol, applied new paste and started the Laptop again.

The Laptop worked fine for about 10 hours, then it restarted out of the blue when I was taking the time to relax and play a game for a while.

My first thought was, well that is strange maybe my PSU died out. I got an another charger from a friend (he has a similar series Toshbia Laptop).

We exchanged chargers for about 10 days. He had no issues, my restarts continued at random.

Sometimes the laptop would work for 3 days, then restart out of the blue. Sometimes it would restart and restart again after 10/15/30~ minutes of gaming after rejoining a game.

So the restarts were truly at random.

Second thing I decided to test out was my RAM.

One of the experiences I had was that sometimes small particles of dust (after cleaning) ended up in the ram and that would cause random restarts. I pulled the RAM out, cleaned it thoroughly.

Afterwards I decided to test out the memory just in case. Booted up Windows Memory Diagnostic, tested the memory, restarted and booted up memtest86 left it on for the tests over night.

The memory had no errors or issues.

I left the Laptop run a bit (thinking well it was probably a dust particle) and the restarts continued at random again.

I've changed memory slots as well.

Don't get me wrong they don't happen repeatedly (unless in a game). Sometimes Laptop restarts 2 time a day, sometimes not at all for a few days. But mostly when I am in game. It restarts in an hour of playing the game (most of the time).

I decided it might be a problem with the CPU or the GPU.

I downloaded Fur Mark and Prime95.

I've done the tests over 2 nights. First night was Fur Mark test time. The test was left for about 9 hours. The Laptop GPU never went above 85*C.

Second night I went on to test the Prime95. Same thing, 85~*C max on the CPU.

I used Fan Speed to track the data into an excel file.

But this time, no restarts (no errors in the meanwhile). I don't know if its luck or something like that. But the stress that was happening should forced the PC to restart if the components were at fault? (Remember, it restarts when I am playing games.)

My final idea, hardware wise was, a faulty HDD. I did tests, S.M.A.R.T. was fine, tests went great. No issues there.

One time after a restart the Laptop pointed out at a faulty BIOS battery. I went and bought a new one. Unplugged the Laptop, removed the BIOS battery, left it like that for 15 min. Put the new battery in and booted it up again.

Even after this Laptop restarted randomly.

Last issue was a possible virus.

I've done following scans:

Windows Defender
Kaspersky Anti-Virus 2017

All passed with no issues at all.

Keep in mind, every piece of software I have installed is open source or payed for. I don't install shady apps or something like that. If something is tested its sand boxed inside a VM.

So guys, any ideas what it might be? I'm out of ideas.

Kind regards,



Dec 8, 2016


Thanks for replying to the topic.

The fan on the CPU cooler, is working as intended. I suspected that too, so I removed my Laptop keyboard (and used an USB connected one) monitored his operation while the PC was working and still it restarted without it doing anything.

A strange thing started happening these past few days, my Windows 10 Clock (including the internal BIOS clock) is loosing its time sync after every restart and randomly during the usage of the Laptop. Since the PC restarts it displays some random time interval between -6 or something hours.

This is the first time I've noticed it, I don't know if it recently started. Its a symptom I think.

Kind regards,


Dec 8, 2016

The only thing I can do is buy another new BIOS battery. But it feels strange, it will be a brand new BIOS battery going bad (exchanged it a month ago). So this would be 3rd BIOS battery in total of the Laptops lifetime.

By the way, in the meantime, the touch pad stopped working. I can't open the Laptop up currently, since I'm working on a project.

But, I wonder if I just forgot to reconnect it (few weeks ago when I checked the fan) or is it another symptom.

Honestly, I'm starting to think that the motherboard is just starting to give up step by step. It's just probably "old" and tired.