Satellite C75D-B7220 - Screen Continually Locks

Question

Hey, Toshiba Support forums, I've had a problem with my laptop since around November, when I purchased the device. My Satellite C75D-B7220 has been locking up on me constantly ever since I got it. While using the computer (from right after booting up the computer at the log in screen to any time during use), the screen, backlight, power button, and any peripheral devices (e.g., a wired mouse) will go dark.
When this problem first arose, I would attempt to hit keys and the power button to turn the device back on, as well as shutting the screen and opening it again. The only thing that seemed to work (and still works) is adjusting the screen until the screen comes on again. The problem is, the screen will stay on from anywhere from several seconds (shutting off again) to an indefinite amount of time. Often, this will happen repeatedly, rendering the computer useless until I shut it off or until it seems to want to cooperate. 
At first, the computer would actually lock, requiring me to put in my password to unlock the computer. This led to much frustration, as I would get half of my password in before the screen would lock again. Now, I have changed all of my power settings to allow for the computer to never lock upon closing the screen, no matter if plugged in or on battery power or on either power setting. This has led to me only needing to adjust the screen so it turns on again and brings me back to whatever I was doing, but has not solved the issue of the screen/power button/peripherals going dead and becoming unresponsive. I have gone into the Bios to allow using the keyboard to wake the computer up from locking, but this has been tempermental at best and does not always work in waking the computer up again. 
This problem is not dependent on what I'm doing with the computer, either - I've had this happen while I was surfing the web, playing a video game, logging in (even before I've logged in), any time. At first I thought it may have been a software issue. I have removed some of the Toshiba proprietary software that came with the laptop, but nothing essential to the computer's function. I believe the issue is either some software malfunction due to the removal of some of the Toshiba-brand software, or more likely a faulty lid actuator switch. My questions are:
What pre-installed software, if anything, interacts with when/how/what happens when the lid closes?
If there is some sort of hardware issue, is it possible to get this computer repaired or replaced?
If you are in need of any more information, such as a list of installed software on the computer or other specifications, or if you all have any ideas or suggestions, I'd very much appreciate the help and would be willing to supply any info I can. 
Thanks,
Ben Piche

Answer 1

Satellite C75D-B7220
The way to tell if the problem is due to hardware failure is to restore the hard disk to its original out-of-the-box contents.
   Settings > Change PC settings > Update and recovery tab > Recovery tab > Remove everything and reinstall Windows
You can keep your logon accounts and most of your data files, by doing it this way.
   Settings > Change PC settings > Update and recovery tab > Recovery tab > Refresh your PC without affecting your files
If the problem occurs before the installation of any Windows updates, applications, or hardware, then it's not due to software on the hard drive.
For warranty repairs, call Toshiba at 800-457-7777.
-Jerry