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Sony Vaio PCG-F420 Troubleshooting
Screen won't turn on
The computer turns on and I can hear that it has booted properly, but the screen remains black.
First try a power reset. This is done by, unplugging your laptop and remove the battery then holding the power switch down for 30 seconds. If this does not work, keep moving through the troubleshooting options shown below.
Look at the screen from another perspective. Is the screen showing any signs of light? If there is any light at all it may be a problem, with the backlight.
Also try cycling all the options on the moniter selection button on the key board. The moniter may be black because it is on a setting that goes to another monitor.
If the probelm persists, then you may need to replace the ballast, the power source of the backlight.
If there is nothing showing on the display at all, you may need to replace your screen.
A key on my keyboard doesn't work
A key is stuck or isn't showing the letter I pressed
A symbol other than the one I wanted is showing up
Make sure your MS Word or other word processor is configured for English and your keyboard layout(usually QWERTY).
Try pressing Fn+F11, Fn+NUM LOCK or Fn+F8.
The key won't move
Use a flat tool to pop off the key. Clean it with some rubbing alcohol and replace.
Nothing happens when key is pressed
You may need to replace your entire keyboard, you can buy a separate USB keyboard to use, or you can open up the virtual keyboard under the accessories tab.
CD/DVD won't play
My CD/DVD drive either won't write or won't read some/all CDs and/or DVDs.
Write down the model of your CD drive. Look for drivers model number on the manufacturer's website. Then download these and install them using the instructions provided.
Use the perscribed lens cleaning solution by the manufacturer to carefully clean the laser on your drive. Also check to make sure the disk is clean.
If none of the other solutions work, you may need to replace your CD/DVD drive.
Floppy Disk won't play
My Floppy drive won't write or won't read Floppy Disk
Ensure that the problem is not a disk by checking that the other floppy disks have the same issue.
Ensure that the right drives are installed for the computer's floppy drive.
If the problems persist, you may need to replace the floppy drive.
Computer crashes when using programs like games or Photoshop
Distorted graphics, blue screens of death or computer crashes when playing games, using Photoshop, etc.
Too many programs running
Press CTRL+ALT+DEL and use the task manager to end non-important processes. If you aren't sure if the process is important, leave it alone.
Your antivirus might have thought a clean file was infected. Turn off any active protection, such as "teatimer.exe".
Not enough RAM
Follow instructions on the installing RAM guide to add more RAM to your laptop.
Computer boots but has an error before opening Windows
You boot past BIOS but you get a BSOD shortly after logging in, you can't get to the login page, or an error comes up about a corrupted file.
First, try to boot into Safe Mode by pressing the key (usually F8) displayed during boot. If this works, do a "System Restore" to roll back your OS to an earlier version. If this doesn't work, perform a "Repair Install" using the Windows disk supplied by Sony.
If your computer turns on but does not boot the OS(operating system) when you press the power button it may well be a bad RAM issue, and you may need to follow install new RAM. The computer BIOS usually lets the user know when RAM is the problem it beeps 3 times.If that is the case you need to replace the RAM.
Bad Hard Drive
If none of the above have worked, you may have hard disk errors. Put your hard drive in another computer and see if it works (make sure to backup your files now if you couldn't do this in your original computer).You may be experiencing a boot file corruption and that can be easily fixed with a recovery disk.Also the hard drive may have been damaged by contact with a magnetic tool and that may have erased the hard drive completely, also a hard fall is enough to damage a drive. Try replacing your hard drive to see if its the problem.