The issue is likely to be one of available space in your system unit, and possibly whether your power supply is man enough. Either by researching or opening up your PC, find out the dimensions of your existing graphics card. Compare those with the dimensions of the GTX750. Also: check the wattage of your PSU, and see what PSU is recommended for the GTX750. At a guess, you won't have a problem - but check it out. Both will be PCI Express cards, so sockets etc. shouldn't be an issue.
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