 The Fastra II 's predecessor , the Fastra I , has 4 dual @-@ GPU GeForce <unk> <unk> video cards , for a total of 8 GPUs . At that time , the ASTRA group needed a motherboard that had four PCI Express x16 slots with double @-@ spacing between each of them . The only such motherboard the ASTRA group could find at that time was the <unk> <unk> Platinum , which has four such slots . In 2009 , the Asus <unk> <unk> <unk> motherboard , which the Fastra II uses , was released , which has seven PCI Express x16 slots . The Fastra II has six faster dual @-@ GPU GeForce GTX 295 video cards , and a single @-@ GPU GeForce GTX 275 , for a total of 13 GPUs . In the Fastra II , the GPUs mainly perform <unk> reconstruction . The technique which allows GPUs to perform general @-@ purpose tasks like this outside of gaming , instead of <unk> , is called <unk> , general @-@ purpose computing on graphics processing units . 
