2.4 i5 or 2.2 i7

Both are sandy bridge. Just curious what would be better for my gaming needs. I'm getting a gt540m and I plan on overclocking but what would be better i5 or i7? Also OS it with $200 more to get an i7? Please answer both. Im looking for an intellectual conversation about this. I know a quad is future proof but I'm looking for more info

which models are you comparing?
what are the rest of your system specs?
a higher clocked dual core would outperform a lower clocked quad core in single threaded tasks but the dual core will lag in multitasking and multithreaded tasks.
if both cpus are mobile dual core core i5 and core i7 then get the i5.
for gaming your gfx hardware is more important.
dual core sandy bridge cpus can play games well. but a quad core like core i5 2500k is better for gaming. you can overclock the 2500k and get extra performance out of it. most games don't yet use 4+ cores and/or hyperthreading so one can save money by getting a non-hyperthreaded quad core core i5 2500k cpu.