Hi Francois,
I see that you are making a gigantic number of operations. And the whole load is on the CPU.
High number of IOs is the effect of relatively small network packet size. sp_sysmon shows only 'Avg Bytes Sent per Packet' is only 2769.
I would try to increase the size of the packet size. This could decrease the CPU load and you can put more connections and more clients. I myself am curious what would be the effect.
Try to increase default network packet size and max network packet size.
Or maybe your test consist just of queries which are retrieving small number of rows?
What type of test client do you have? java? isql?
Do you have the any results from monSysWaits? Poll monSysWaits, wait 1 minute, and poll again.
regards,
Adam Leszczyński