Some stats @http://hvc.nonce-pool.com:
Intel Q6600 Windows ~64kh/s
Intel i3-2100 Windows ~86kh/s
Intel X3450 Linux ~72kh/s
Intel E3-1230v2 Linux ~184kh/s
And my contribution to the list:
i5 3360m (Win7 64bit): ~72kh/s
Phenom x4 955 (stock 3.4 Ghz): ~85kh/s
I think that is low kh/s for i5. Try updated miner