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I have to reset (unplug, replug) CMOS every time I startup my laptop otherwise it won't power on. HELP!

  • Laptops
  • Fan
  • Power
  • CMOS
Last response: in Laptop Tech Support
September 13, 2017 1:17:02 PM

It all started with a problem at the fan. It started making very loud and unusual sounds and the laptop started overheating a lot. I had over 100°C temps and super lag in games(also 80°C when idle). I decided to disassamble the laptop and fix the fan/clean up the laptop. I managed to fix the fan, got every particle of dust out of the laptop, even took out the motherboard and the heat pipes so i could apply some therm paste on the cpu and gpu. Only when I assambled it again, it wouldn't power on again. I tried many many things from the internte and finally... i stumbled upon a forum about removing the CMOS battery and pluging it back (also the 30 seconds static discharge). It worked, i was happy the laptop got into windows again, tho i felt something was strage. Only then i realized that the "Asus" logo followed by the bios startup messages were skipped and the laptop logged it straignt into Windows. I shut down my laptop to see if it would happen again. But the laptop wouldnt power on again. I opened the case again and repeated the CMOS techique. And apparently now i have to do this every single time when i want to use my laptop, and every time, it skips the bios messages on start up. I also noticed some delay sometimes on my wireless keyboard. Tomorrow ill buy a new battery to see if it changes anything.

Do you think that will fix it? Could it me a faulty motherboard?

PS: The overheating problem is over at least. I get 30-35 degrees on idle, and about 70-85 in games.

More about : reset unplug replug cmos time startup laptop power

Best solution

a b D Laptop
September 14, 2017 10:28:42 AM

I am glad to hear it has at least powers on and shows some life and usability because the other threads I have read when people who have risked this themselves never saw the laptop power on again. There may be a small short on the board that in the sense seating of the motherboard needs to be checked again but I would go with your method of replacing the cmos battery first with a new one before full disassemble of the motherboard.

If the cmos replacement fails to fix it then open up the laptop but first use a magnifying glass and check if the gpu is properly soldered to the motherboard and as well as the cpu (unless cpu is like a desktop and removable) . There may be small hairline cracks causing intermittent power issues. Also try removing the ram and replacing it.
September 22, 2017 7:52:22 AM

Sorry I have been away for the holiday but yes, it does power on every time i removed the cmos. I was in a bit of a hurry and needed the laptop a lot for 3 days and had no time to send it to an analysis at a computer shop. Because i needed it i kinda avoided disassembling the laptop every time, by dragging two cables from the cmos port on the motherboard outside the laptop and i was easily able to link the cables to the battery and deatatch them every time i needed to work. Now that i decided building a pc in like 3 months, i was woundering if the little trick with the cables i made puts the laptop in any danger of frying the board or can it be used like this for the remaining months.
a b D Laptop
September 23, 2017 9:39:16 AM

Well technically speaking if the battery is the correct voltage then no it should not damage anything if you are absolutely careful.
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