ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

[486junkie]

Here's the story (should've gone on this forum years ago):

My ASUS X54C-RB01 is having issues with power cycling when turning it on (cold boot), rebooting an OS (Windows or Linux), or saving changes and exiting the BIOS.

The cycle when turning on the laptop is this:

Power light is on steady, as well as the charger light, num lock and HDD lights turn on briefly, and turn off, repeats, and turns on fully (shows the ASUS logo, the boot screen choosing between Windows 10 Pro and Xubuntu 17.10.1 LTS) and works normally.

The cycle when rebooting the laptop from either the OS or saving and exiting the BIOS:

Power light is on steady, as well as the charger light, num lock and HDD lights turn on briefly, and turn off, and the power light turns off and on again, repeats, and turns on fully (shows the ASUS logo, the boot screen choosing between Windows 10 Pro and Xubuntu 17.10.1 LTS) and works normally.

Also, the battery was draining rather quicker than before the issue started (goes about 1.75 or so hours and it dies), but, after a calibration, the battery is back to normal, but, Windows reports the battery has 1 hr and 45 min at 97% with the charger disconnected. I opened up the laptop to look and see what's going on, and I found out the screws for the heatsink/fan combo wasn't tightened up, so I tightened up the screws, and still no dice. I also notice the fan doesn't spin up when the laptop is powering up when it's supposed to. Wish I had the proper multimeter to check the capacitance of the SMD caps for any issues since the probes on my current multimeter are too big and slip easily.

Could it be a motherboard or capacitor issue? The I/O works without issues, it's the power that's not working properly (the polarity for both the battery and charger is at full continuity).

Specs:
Motherboard: ASUS K54C 2GB RAM Soldered on (Max: 6GB)
CPU: Intel Celeron Duo B820
GPU: Intel HD Graphics
HDD: Inland 480GB SSD
ODD: DVD Burner
Display: 15.6" 1366x768 (VGA and HDMI output as well)
RAM: 2GB soldered, 4GB DDR3L (6GB total)
Sound: Intel HDA
Network: Atheros Gigabit PCIe Ethernet, Ralink Wireless N
Chipsets: Intel (not sure what the model numbers are)
Battery: Standard 4-cell ASUS OEM battery
Charger: OEM ASUS Charger 19W

[caspian]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

have you replaced or changed any hardware in the laptop before the problem arises?

[486junkie]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

have you replaced or changed any hardware in the laptop before the problem arises?

The processor I kept as-is, wireless card as-is, and the only things that were upgraded or swapped was the RAM from 2GB to 6GB, heatsink/fan combo back in 2013-2014 since the old one broke, and the HDD to an SSD back in 2016

[caspian]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

test the laptop using only one RAM stick.

[486junkie]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

Tested with one stick, did the same thing. I cleaned the CPU and heatsink with new thermal paste, sprayed DeoxIt onto the CPU socket and RAM socket. The laptop almost boots up the first time (I hear the optical drive spinning up, which is a sign), but, it's still acting up. Going to purchase a soldering iron that's meant for SMD everything, remove one cap at a time, and test them individually using an LCR multimeter to see what happens.

[486junkie]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

Bought an LCR Meter, checked every capacitor, and about 6 capacitors are bad and the others are reading higher levels.

Capacitors:
1x 2D3 220uF 6.3V SMD (bad) --> 25uF (might be wrong readings)
6x 68 EFK. C42 25V SMD (over) --> increments between 525uF-526uF (might be wrong readings)
5x E246 560 2.5V SMD (bad) --> increments between 114uF-300uF (might be wrong readings)

I cannot seem to find the 560uF 2.5V SMD capacitors anywhere and cannot get them from overseas due to charging more for shipping than the caps themselves.

[mcplslg123]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

i think,though not sure, 560uf caps are there in HP G6 R12/13 series mb. Look for it if you have any scrap mb.

[caspian]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

Cheap LCR Meters are weak in measuring nonpolar capacitors. thus any approximate reading may indicate that the capacitor is probably not faulty.
how old is the mainboard?
are the capacitors looking dark or cracked?
a photo of them could help.

[486junkie]

Re: ASUS X54C-RB01 issues: power cycles during cold boot or reset/exiting the BIOS

The board is 6 years old and the LCR meter was $25. Some look a little bulky on top.