janneauclaude :
Hey guys I was wondering which one is the better one?
That's a very tough question because YOU DIDN'T SPECIFY WHAT YOU PLAN TO USE IT FOR AT ALL
So here we go:
It depends on what you wanna use it for.
If most of your work includes light-multithreaded applications like web browsing, photo editing, gaming then the i5 crushes the FX, maybe the FX can match the i5 with overclocking.
If your workflow is primarily heavily-multithreaded like video rendering, 3D rendering, video and file compression, live streaming of maybe doing all this stuff at the same time then the FX CPU runs a bit faster.
I would still get the i5 though, the FX CPU draws a lot of power (high electricity bill costs) and it is barely faster than the i5. Despite having double the cores and higher clocks, cache, etc that doesn't mean anything because the arquitecture (the way the CPU is made) is CRAP so the i5 processes much more data per core and per gigahertz. Also you can overclock the i5 2500 not to much but make to 3.9 GHz with a P67 board and BCLK adjustments and whenever you feel 4 cores is not enough you can upgrade to an i7 3770K which is much better than ANY FX or APU processor released to date.
But it power consumption is not a huge concern (which always is) the FX gives you better multithreaded performance if you need it.