Have a HP DV9420US laptop running Windows 7. Have an external year old AOC LED monitor hooked up through VGA port. All has been working fine for about 1-1.5 years. Suddenly AOC external monitor colors went bad but laptop colors are fine. Hooked AOC monitor up tp a Dell Latitude D830 and it has fine colors. Looks like to me that the VGA port or connection may be bad. What do you think may be the problem and what can I do to fix this problem? Or can you lead me to a solution,please. I have added a copper heat sink to this laptop as HP had a bad design with these models as you all know. Since adding this copper heat sink about 2 years ago it has been running fine. Had Laptop probably about 5-7 years.
Thanks for any help and advise you could give me!
Check to see if any of the VGA pins are bent over, or missing.
No pins bent. Checked male and female ends. Switched cable end to end no change. alptop has been of for over 24 hours to se if it may be heat problem no change. If there was anything wrong with cable or pins then it wouldn't have worked with the Dell laptop. Thanks for the reply and keep suggestions coming. This has me stumped.
Same problem if you plug a different monitor, (not the AOC), into the laptop?
Yes Sir same problem when I plug a different monitor into the HP laptop.
Then as you suspected, it does sound like the problem lies behind the face of that laptop's VGA port somewhere.
But wait, before you start tearing it apart, does it exhibit the same problem in Safe mode? If so, the problem is not hardware but some of the software that is running when Windows is running in Normal mode.
If still exhibits the same problem in Safe mode though, try running a different OS, such as any Linux Live CD|USB. If it runs okay now, then again, the problem must not be hardware, but Windows itself. Run "chkdsk c: /r" then a "sfc /scannow" to start.