All depends on budget and the final hardware requirements for GTA5 but this will have you covered.
If you want to overclock the CPU then get a 4770k instead of the 4770.
You will probably need to swap and change a few things depending on availability from your local retailer/etailer
YOUR BASKET
1 x Intel Core i7-4770 3.40GHz (Haswell) Socket LGA1150 Processor - Retail £239.99
1 x Asus HD 7970 DirectCU II TOP 3072MB GDDR5 PCI-Express Graphics Card **FREE SHIPPING** £239.99
1 x Patriot Viper "Black Mamba" Generation 3 16GB (2x8GB) DDR3 PC3-17000C11 2133MHz Dual Channel Kit (PV316G213C1K) £129.95
1 x Gigabyte Z87M-D3H Intel Z87 (Socket 1150) DDR3 Micro ATX Motherboard £97.99
1 x XFX Pro 650W Core Edition '80 Plus Bronze' Power Supply £71.99
1 x BitFenix Ronin Tower Case - Black £69.95
1 x Noctua NH-D14 Dual Radiator CPU Cooler £65.99
1 x Western Digital Caviar Black 1TB SATA 6Gb/s 64MB Cache - OEM (WD1002FAEX) HDD £64.99
1 x Asus Xonar DX 7.1 PCI-Express Sound Card £59.99
1 x OcUK 24x DVD±RW SATA ReWriter (Black) - OEM £14.99
Total : £1,055.81 (includes shipping : FREE).