Something to also make a metal note, even though I loved the sabertooth, it was only pci-e 2.
New haswell boards are pci-3 and this will help in the future for gcards a lot, otherwise you will start to bottle neck the gpu.
My best advice from having both, is to buy whatever i5 you can afford on a cheap non overclocking gigabyte mobo, and pair it with whatever your budget will allow, also haswell supports avx2, amd only avx, this may also impact greatly in the future.
look up benchmarks for them both, I will link some when have more time.