Does the graphics card itself work? Does he get an output on his monitor?
Make sure that the fan is plugged in correctly. Also make sure that your friend has connected the additional molex connector to the graphics card if it requires one.
Other than that, if the card work (though I wouldn't have the PC on too long, don't want to overheat the gfx card) he could either RMA it, or buy a new heatsink and fan to replace it.
|Desktop PC| |Macbook Air 13" (Mid 2013)|
|Windows 8.1 Pro (x64)| |AMD FX 4100 Black Edition 3.6 GHz @ 4.0 GHz OC| |Arctic Cooling Freezer 13 PRO| |Gigabyte Nvidia GeForce GTX 560 Super Overclock 1GB| |ASUS M5A78L-M/USB3 Motherboard| |Samsung 840 Pro 256GB SSD SATA III HDD| |Kingston HyperX 8GB PC3-14900 DDR3-1866| |OCZ ModXStream Pro 700W Modular PSU| |NZXT Vulcan Micro ATX Case|