The VF900 doesn't come with the same 3-pin to 4-pin molex converter that the VF700 uses.
The manual actually says to plug it in to an available 3-pin motherboard fan header:
VF900 Manual
Of course if you don't have an open header you can always use a 3-pin to 4-pin molex converter and...
I was referring to your 3dMark freeze. An unexplained lock-up usually brings into question stability of the system, but maybe it's not a big deal. I was just trying to make you aware of a common problem with those PSU's.
Not sure if this will help with your performance, but you did mention some stability issues:
http://www.silverstone-usa.com/QA-POWER.htm
That page references the 7800GTX, but I believe it was published before the 7900 series was out, so it may apply to you.
I believe they mean it has "replaceable" ear cushions. Meaning you can buy replacements later down the road. My 485's certainly didn't come with an extra set of ear cushions.
I'm using the following KVM with a Logitech USB "Media Keyboard Elite" and a G5 mouse with good success. The additional multimedia keyboard buttons seem to work fine and all of the additional buttons on the mouse function as expected. I will say that this KVM can be a bit finicky sometimes...