Sometimes you'll have an out-of-warranty video card that is basically now a paper-weight.
If you were going to throw it out anyway and you have an oven and common-sense you have a chance of temporarily repairing the card/chip by re-flowing the solder or heating the bumps under the Surface-mount chip. Obviously as with any guide that involves an oven you might burn your house down or burn your hands or inhale toxic fumes or whatever, please don't do anything that you don't feel comfortable doing.
However if the warnings don't scare you, continue through the guide.
Please note that the guide has been edited by a few people over the years - some parts are not my original writing
Graphics card circuit boards can have bad solder joints or bumps under the GPU surface mount chip which can sometimes be temporarily repaired by heating the chip and board in an oven