The GeForce 6 or 7 is quite old. So far, there have been GeForce 8, 9, and the GTX series. Given the age of the PC, you may not be able to upgrade to the latest and greatest GPU, but you can at least get one that works. In order to determine if you can use a new graphics card, we need to know more about your system. One of the simplest ways to determine which motherboard you have is to run CPUz. You can download it here
. Run the program and it will give you information on the CPU, but if you click on the mainboard tab, it will list all of the motherboard (a.k.a. mainboard) information. Tell us, or take a screen shot, of what it says there. However, if the PC is not working, you may have issues in running this software. You can send us the model number of the Dell PC and we can look it up. Typically, there are two different types of graphics card slots in a PC and you have to get the right one. This
is an AGP slot. The brown socket at the top is AGP whereas the white ones are standard PCI. AGP is older and has been replaced in most PC's by the PCI Express slot. In this
image, the two longer sockets are PCI Express x16 slots. If your PC has neither of these slots, AGP or PCI Express, you may be limited to standard PCI cards. Also, if you're going for a high-end graphics card, you will need to know the wattage of your power supply. That cannot be determined through CPUz, but there should be a sticker on the back of your computer that will list the wattage. Typically, it is located on the back of the PC.