|Monitors or built in displays don't boot. |
They either produce a display or they don't.
Some will display a text message after a brief time if they are not getting a video signal - I'm assuming what you mean is the screen is black - no video at all.
Operating systems load.
"..."i have tried connecting the laptop when the monitor didnt boot up and there was no signal."
Would this be a better description of what you should have said ?
"....i have tried connecting AN EXTERNAL MONITOR TO the laptop when I GOT NO VIDEO ON THE BUILT IN monitor and there was no signal. ??
If so, as I said in my previous info, you may need to press a key combo to get a display on the external monitor - see you Owner's or User's manual.
"....sometimes the LED that flashes when the laptop is on does not and this is when the monitor does not work."
Which monitor - the built in one ?
Which led ? If it's the hard drive activity led, it doesn't flash all the time, and if the hard drive stops working properly while it's not producing a display while it is supposed to be loading Windows, you can have nothing on the built in screen, but you should have video while booting before Windows loads in any case, unless the built in display is failing for whatever reason (there's usually nothing wrong with the video adapter).
If all the other leds are working fine, the hard drive activity led never comes on even when you try doing something at that point, test the hard drive with diagnostics.
(If you have a charging led, it goes off when the battery is fully charged.)
For that matter, test the hard drive in any case.
BEFORE you test the hard drive, it's a very good idea to test the ram to make sure you're getting no ram errors.
If you want to try a memory diagnostic utility that takes a lot less time to run a full pass than memtest86 does, this one is pretty good - Microsoft's
Windows Memory Diagnostic:
Windows Memory Diagnostic is limited to testing only the first 4 gigabytes (GB) of RAM.
It can be toggled (press T) to do a standard or a more comprehensive set of tests - use the default 6 test one first - if it passes one pass of that, use the latter one. A few of the tests in the latter set are intentionally slower.
If you don't have a floppy drive, see the Quick Start Information at that Microsoft link for how to make a bootable CD of the Windows Memory Diagnostic (you need Windiag.iso - you don't necessarily need to use the program they mention to add it to the CD).
If you DO get ram errors, it's probably because the ram has a poor connection in it's slot(s). Remove the main battery, unplug the AC adapter from the laptop, remove the ram, wipe off it's contacts with a tissue or soft cloth, install the ram properly. See your Owner's or User's manual for your model if you need to know how to do that properly.
Then install the main battery, plug in the AC adapter, and try the ram test again - it should pass just fine.
The first things I do when troubleshooting a computer that has problems, when it does have video, is to test the ram and the hard drive.