This is one of my liquid cooled Lian Lis:

Components
Intel Core i7 2600K
ASUS Maximus IV Gene-Z
4x4GB G-Skill DDR3-1600 RAM
Powercolor Radeon HD6850 Passive
Corsair Force 120GB SSD
Pioneer DVR-218LBK DVD Writer
Antec EasySATA hot swap bay
Corsair AX750 PSU

Cooling
Swiftech Apogee XT
Swiftech MCR320
Swiftech DDC3.25 w/Koolance COV-RP400 top, running @ 7V
3xScythe S-Flex E @ 5V
2xNoctua NF-P12 @ 5V

Notes
It was a long journey to get to this point, and it's not over either. I am trying to decide what video card to put under water on this setup.

This setup is very quiet. I turned off all fans/electronics in my house and it is almost not noticeable.

My original configuration called for 3xScythe Gentle Typhoon 1850RPMs wired for 5V, but the motor growl and frequency beats of three drove me up the wall.
Prior to this, I had used a Danger Den DD-CPX1 pump which is silent if decoupled properly, but it was transmitting an audible hum that nagged at me. It prompted me to switch out for the DDC3.25 and the Koolance top.

The CPU is overclocked to 4.8 GHz @ 1.425V set in BIOS, and in LinX w/AVX it peaks at around 85C. The PSU sometimes emits a light squeal here and there, but it is not very noticeable.

The loudest part of this setup is the semi-soft mounted Noctua acting as the rear exhaust.

With the side panels on, this thing looks almost like a regular stock A05NB, except for the wooden feet I've added to give the bottom mounted radiator some breathing room.

I still have to sleeve and tidy up the pump cables.

Who says watercooling for silence is a dead scene?

Well, here we go back to AIR.

Here is what prompted the change:

1. Changed my SmartUPS1500VA for an older version without a constant fan running = lower noise floor
2. I had a GTX580 for a while, but sold it off as I'm not gaming as much before = lower noise floor (even with the fan running at 30%, which is pretty quiet for a high-end card)
3. Changed the tubing around the pump for some softer Tygon to reduce pump vibration transmission
4. Run the pump at 5V

After a while, my pump no longer started at 5V (borderline inaudible), due to what I suspect is an air bubble in my loop (due to draining/re-filling with the softer tubing). I got frustrated, and just wanted an inaudible PC. Managed to get a very good deal on a Noctua NH-D14, so I decided to test it out.

With both CPU fans at 5V, as well as a 5V S-Flex E on the 6850 SCS3, and a soft mounted P12 on the exhaust, this computer satisfies my requirements of 'inaudible difference when on vs off'. I can detect a hint of vibration from the case with my ear less than 6" from it, but from 1ft+ I cannot hear it.

I'm very lucky that the NH-D14 clears the SCS3 heatsink.

The CPU overclock is less agressive @ 45x100, 1.325V. Under full load it reaches 85-88C which is acceptable to me. Next steps is possibly move the PSU back to its normal location and block off the bottom cutouts (or cover it with some kind of filter). You may notice that I've also switched back to my P8P67 Deluxe.

That's pretty high. Have you considered flipping the GPU fan so that it sucks air through the fins and blows it upwards? That way you won't have warm/hot air being blown downwards onto the CPU heatsink.

Lian Li makes a top cover with a fan cut out. Try it. It will be a big help in getting the temps down. Otherwise heat tends to build up at the top of the case.