07-12-2018 06:02 AM
I have an Ideapad G510 with Intel i7-4700mq, intel graphics running Win 10.
Recently it will not power on or boot. With the battery installed, and the power supply plugged in, the battery charge LED is on.
When pressing the power button, the power LED comes on for approximately 5 seconds and then goes out. Nothing appears on the screen, the fan does not come on, no beeps, nothing.
THEN: after leaving for a random amount of time (hours), the machine will boot itself (without anyone touching it), at which point it seems to operate normally. When it is running, it can be restarted any number of times and works fine, but if it is powered all the way down (ie shutdown), the bad behavior starts again and it will not power on again when the power button is pressed (power light comes on and goes out after 5 seconds or so as before).
When the machine was booted OK, I rebooted it with the UEFI diagnostics on a USB stick, and it passed all the tests ok, with the exception of the Real Time Clock (suggested replacing CMOS battery). Ran the tests again, and this error did not recur, however I replaced the CMOS battery with one from another laptop, and this made no difference (didn't think it would).
I have tried with/without the battery, and also with another Lenovo power supply and this does not affect things. Reseated the ram sticks. No help.
Any ideas? (maybe flakey motherboard?) The starting by itself thing after hours of waiting is bizarre though...
07-22-2018 11:21 PM