I did a quick search around for some comparisons, and came up with this one:
AMD's Athlon 64 X2 6000+ processor

Like many it is a little dated, and although does not compare the 6000+ against the e6320, it compares it against the Intel E6700 which has the same bus speed, the same size L2 cache, but runs at 2.66 GHz rather then the 1.86 GHz the e6320 runs at.

chaosclown , have you noticed any compatibility issues between AMD and ATI ( would be very embarrassing for AMD since they own ATI ! )

Your bottlenecks will be in other areas.
I would definitely be looking at the other components such as motherboard, memory ( both speed and amount ).
If these are bundled systems, the hard drive speeds and seek times as well as the interface ( EIDE or SATA ).

Then there is the graphics slots, etc., but you get the idea.

Just remember, that AMD is going to take more power and run hotter, so make sure you account for that.