Bad performance, what did I forget?

[Creazil]

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Run keyclone, run clients 1-5. Entire computer freezes on loading client 2 (on 2nd monitor).
A single press of ctrl-alt-delete forces a reboot.

Reboot, try again, 1 client at a time. First client loads fine (on 2nd screen). Second client, keyclone gives an error about buffer overflow and closes.
Exit client 1, retry keyclone, client 1 loads fine, skip 2, client 3 loads fine, client 4 causes entire computer to crash like earlier.

Reboot, try again without keyclone. Client 1 causes entire computer to crash, this time giving me a blue screen with a stop: error.
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http://forums.nvidia.com/lofiversion/index.php?t82311.html

The problem is the same for the new driver. Aka windowed mode + a few other things makes it fail.