I've had this gaming laptop for nearly two rears now, and it's running an HD Radeon 6990 dedicated graphics card and an integrated Intel graphics chip.
Lately the dedicated graphics hasn't been working. Sometimes I'd turn on my computer and play a game to find that it won't run due to the integrated graphics not being able to handle demanding games. Other times I turn on the computer and the dedicated graphics can be seen and games can be played at normal performance.
However it's been over a week now and the laptop still can't recognize a dedicated card. I've looked in Device Manager numerous times and in System properties, and only the Intel integrated graphics can be seen by the computer.
I would rule out the software in efforts of not wasting time.
1 - Check the Bios and determine if the card is disabled somehow (depending on model, unsure of the bios entry key). Usually F10, or esc. You can also find a setting to trigger "reset to defaults" and save, boot up again
2 - Back up the files and...
Do a factory restore on the unit, or with the oem discs. Then double check the device manager.
3 - If its the same issue, then i would suspect a HW issue. Hopefully its under warranty? (pays to get it on laptops)
if the 6990 is on its own board it might have come a bit loose from its slot giving you contact problems. If it is soldered straight to the main mobo it's probably toast (cracked solder joints and all that)... So take a look inside and make sure it is firmly in the slot if it's indeed a separate board.
Soldered gpus can be fixed by baking/reflowing them again but this should be the last thing to try... (not a quaranteed method and the fix is most likely temporary at best) http://www.anandtech.com/show/6840/hardware-tricks-can-...
(works with gpu cards/boards/modules as well naturally, even easier since the board is smaller etc)
Also another problem that I've been having lately which I now believe is related to my graphics problem is the computer won't start up correctly if I restart my computer or boot it up within a couple of hours of shutting it down. What happens is that the computer goes through the start up process all the way to the windows starting screen but when it finishes loading and looks like its about to transition to the log in screen, the screen seems to turn off and won't progress any further. The only thing I can do is shut it down, wait for a few hours and hope that it starts up normally after a long enough break. I have tried startup repair and system restore at in startup repair but it never fixes anything.
This problem first started a few weeks ago when I was playing Napoleon Total War for a few hours and suddenly the game crashed. The screen had blue and grey vertical lines across the screen, but the audio was playing normally. I couldn't alt-TAB or ctrl-alt-del out of the game so all I could do was shut it down. I restarted the computer and then the game again to see if the problem was related to the game. The game started up ok, but it crashed again when I tried to resume from the last save, this time with green and grey vertical lines. After shutting it down, and restarting it again is when the problem of the computer not starting properly first happened.