my favorite build for absolute budget gaming is with a cheap socket 1155 H61 mobo, a pentium G840 processor(its a touch slower than the i3 2100 and doesn't have quicksync), a 4GB dual channel kit of ddr3 1333, cheapest case power supply combo. which leaves me about £100-£150 for video. then get the best card you can. you should have enough for either a radeon 6850, 6890, 6950 or a GTX 560, 560ti.