RobCrezz :
What PSU do you have already? One of the main benefits of the 750 ti is that it uses so little power you often can use the same psu.
This is the PSU I have:
Model No.: ISO-450PP
AC INPUT: 230V,4A,47-63HZ
DC OUTPUT: +3.3V ---- 20.0A (ORG),+5V ----- 32.0A(RED),+12V ---- 16.0A(YEL)
+5Vsb ---- 2.0A(PURP).+5V ----- 0.5A(WHITE),+12V ---- 0.5A(BLUE)
FUSE RATING: 5A,250V ~ (+3,3V & +5V=200W Max)
MAX OUTPUT POWER: 350W,(+12V,+5V&3.3V TOTAL)