Is it possible for a malfunctioning video card to prevent the OS from loading?

Sometimes when I switch on my computer, there is no output to the monitor or the speakers even though everything seems to power on; the lights go on, the PSU and CPU fans are spinning, the drives seem active. If I then switch my computer off and on again, it will startup correctly, though it sometimes takes a few tries. It will then run perfectly until I restart it again.



I'm inclined to think it isn't merely a video issue, because I would expect to hear the vista startup sounds after a minute if that were the case. However, there is one component which is visibly malfunctioning, and it is the video card; the fan doesn't spin.



Is it worth it to buy another video card just to see if that is the problem? Or am I correct in thinking it can't be the video card?|||You could try removing the graphics card from the motherboard, and plug the monitor cable into the motherboard video socket (probably be a VGA/DE 9 or 15 socket ... Or the blue socket in the back), and then try to boot. If the computer works, its the video card. If it doesn't, its the motherboard.|||If you can see the post screen( the screen that shows your brand of computer) then it could be a video card issue. If you do not see the post then it could be a memory issue. If you have two sticks of RAM installed remove one then try to boot up, if no luck then put one back in and remove the other. If you find that it boots after removing one that you will need to replace the bad one. Another thing you can try is updating the drivers on the video card. Hope that helps!|||The only advice I can think of is to first, make sure that you have a powerful enough power supply (Probably do) then, take out the video card, clean it and the slot, reseat the video card in the slot and make sure it is seated as perfectly as possible. If there is some interference with the power supply getting to the video card, the motherboard will prevent the computer from booting. The same thing would happen if for example your ram was not properly inserted all the way. If the card is properly cleaned and seated in the slot then I would assume either the card is defective/malfunctioning or the motherboard is.



Oh, you've probably already done this but you may want to check to see if the video card has it's own power cable from the power supply. If it does, then you should obviously make sure it is hooked up.