I'm using Acer 4637Z, running Windows 7. When I turn on my laptop, it will unexpectedly turn-off at start-up. The hard disk light blinks normally prior to start-up. Virus scan is clean too.
Please advice
This could be probably the cause from over heating or boot failure
There's something that's preventing your system to start
In order to solve this, you might want to start a System Recovery
or Format the system if possible
This may be a longshot, but is the cooling fan working? I had a the same problem with one at work and removed the keyboard to find the fan had jammed, after freeing it it booted fine.