Acer Aspire 4736G constantly shutdown by itself without warning

I have a 6 years old laptop that is constantly shutting down by itself without warning during startup.

This happened after I downloaded an ebook.

The shut down occurred more during starting up the laptop about 6 times before reaching the logon screen.
It normally shuts down a few times in normal use like surfing the web, downloading, or even when I was running hardware tests or HDD error checking.

At first, I thought the Toshiba HDD was nearing it lifespan. I did a test on the HDD. Please read 6 yo Acer Aspire laptop can't boot due to sysconfig changed & disk err. The constant shutdowns that occurred, damaged the Toshiba HDD severely especially the MBR.

I already performed Windows MemTest.
All OK, normal bootup without any problems.A pop sound!.Shutdown again after 25 minutes of use.

In safe mode, no shutdown yet in a minute or two. I did not keep the Acer power on in Safe Mode for more than 5 minutes.So the test is inconclusive.

Then I did a re-installation of windows 7 on a new Western Digital HDD. Please read I am totally blank on installation of Windows 7 on a new HDD.

After re-installation of windows 7 on a new WD HDD. The new WD HDD will auto shutdown every time during startup or bootup even before reaching the logon screen or after I logged in or when I was installing the drivers 10 to 20 minutes after startup or bootup .

I am now using the old Toshiba HDD to access the WWW.

Did search using google, next going to clean the fan.
Maybe BIOS,RAM or mobo problem?

Any ideas?
Thank you again for your replies.

Thank you TVeblen for your reply.

The good news is that the 2 RAM sticks are fine but the bad news is the Acer laptop is totally unusable as both the old Toshiba HDD and newly installed WD HDD both cannot bootup at all.

Once the booting is on its way, pop, the system shuts down.The old Toshiba HDD MBR can be construed as damaged by the constant auto shutdown but not the newly installed WD HDD.

So it is a hardware problem.

Which hardware is defective, I really don't know?.


The BIOS is Insyde2.0.I am not sure if I spelled it right.The main page of the BIOS don't show any temperature at all.
No changes can be made.That's odd.
The BIOS cannot save the changes I made after many attempts using the F10 key.

Can BIOS be infected or corrupted by malware?

I am proceeding to disassemble the Acer 4736G laptop to clean the fan.

TVeblen said:

Ah. Please be aware that your "My System Specs" say it is a desktop. You should change that.

Thank you for telling me.I am so listless.

TVeblen said:

Sounds like a power problem.

Can you get your hands on another power supply to test with?
Do you have a multimeter you can use?

Could also be an overheating or a CPU fan problem.
Check that the CPU fan header is plugged in properly, then watch the fan at startup for any hiccups.

You can also boot directly into the BIOS settings and go to the monitoring section (different on every MB) and check your temps and voltages, at start - in 15 min - at 1 hour. See if there is any notable changes.

Well the PSU adapter is in pretty good shape.
I used another PSU adapter, still the same problem.

It could be the fan or overheating.

TVeblen said:

Yes, laptops have very limited BIOS settings. There will be no monitoring section there.

Theoretically a BIOS can be infected with malware - it has been demonstrated at shows - but all I know of require human interaction (a guy at your PC with an USB stick). Never heard of an infection in the wild.

What BIOS settings are you trying to change that will not take?

Have you tested the laptop with the battery removed? Remove the battery and use the power supply/charger only. See if that changes anything.

The laptop totally cannot be started since Wednesday with the old or new HDD. I am using my father's laptop to access the web.

cyrilhubert said:

'I am now using the old Toshiba HDD to access the WWW'

no longer holds.

The pop is unbelievable!
Once I powered on, popped! off it went.

TVeblen said:

"What BIOS settings are you trying to change that will not take place when the laptop was still working?"

The boot sequence changed from booting HDD first to DVD first cannot be saved at all. I was trying to use the repair disc.

TVeblen said:

Have you tested the laptop with the battery removed? Remove the battery and use the power supply/charger only. See if that changes anything.

Done that, the laptop still went off immediately.

Hitting rough patches along the way. In disassembling the laptop, a screw cannot be loosened. I am stuck right now.

Thank you for your concern and replies.
Very much appreciated and grateful.

I am sorry for my late reply as I have problem accessing the WWW.
Yes, I hear a popping sound every time before the laptop shutdown without a warning.