No video I can turn on the computer and my monitor says check cable and computer monitor working regretfully a regular video card will not fit in this version computer if this is the problem where do I purchase a new video card

It's not necessarily the video that's the problem. Anything that would keep the computer from beginning the POST process (beginning of the process of booting your computer) could also result in no video. When you start the computer up, does it beep at all? If so, how many beeps, and are they long or short. The order and lengths of the beeps are the most basic type of error codes. Also, do you hear the hard drive spinning up? And does the CD/DVD ROM drive start up normally? It could be a power supply, your processor, memory, the motherboard or just the video card. It could also be just about anything in the computer if it developed a short, as a single short can cause the power supply to shut itself down so as to protect the computer from being further damaged. I would suggest disconnecting power to the drives, and trying again. If it boots to video, you know one of the drives is the culprit. If they aren't the problem, try removing the memory. It won't boot that way, but if the memory is the problem it will at least reach your POST and give you the option of entering BIOS. If you get that far, the memory is at fault. Then, try the same with any expansion cards onboard. If none of that causes it, then you either have a bad processor, bad onboard video, something else wrong with the motherboard, or bad power supply. Unfortunately, none of that can really be tested without having parts to swap out.