I think one side of the problem could be the way the air i blown.
I have a similar setup, with an totally watercooled pc with qx9650@4GHz and 2x AtiHD3870, 2x ram, nb, sb and 2x Aquadrive dual. 1 Thermochill PE120.3, 1 BlackIce Stealth 240 and 1 Thermochill PE120.1. The rads is cooled by 6 Noctua (NF-P12-1300)
[img]http://www.diskusjon.no/index.php?act=attach&type=post&id=227247[/img]
My aquastream XT Ultra run at 70l/h (compared to 85l/h with two Laind DDC-1t in series).
When I was blowing cold air from outside the box in over my rads ( I was really blowing hot air into my case, due to the heat transfer from the radiators), I noticed that some of the heat was recycled, and that temps was gradually increasing inside my case.
Thus, by turning all radiator fans, so that they blow "hot air" from the inside case and out, my system runs much cooler. And I lovered my watertemp by 7-10 celcius (runs now at 31-32) with fans at 50%.
Mobo has temp of 40 idle to 50 full speed, and cpu 35 (45 on the kernels) idle and 50 (60-65 at the kernels) at full speed @4GHz.
More pictures can be found in my worklog (norwegian):
http://www.diskusjon.no/index.php?act=at…=post&id=227247