Other potential cases: Fractal R4, Antec P183 v3, Corsair 550D, Nanoxia DS1. If you like $250 cases, consider the Silverstone FT02. It'd beat the pants off the Lian Li for noise.
Thanks! I'm not really looking for $250 cases but unfortunately the only one with five 5.25" bays and a door was in that price range. By far the most expensive case I've ever bought. I looked very closely at all of the cases you mentioned above but none met the five 5.25" bays and a door requirement. I even thought of trying an external pedestal (ie, something like a mini P18x with nothing but 5.25" bays) but haven't found such a beast.
GDDR5 based AMD graphics cards don't idle/downclock the memory when using more than one display. So, it'll burn 20W when the equivalent Nvidia uses 10W. The highest end fanless Nvidia appears to be the GT 640. Asus and Zotac have models. A potential downside to the GT 640 is it's GDDR3 memory. Photoshop uses the GPU to accelerate
some functions. The slower memory in this card may castrate the benefit. Also, is you wanted to move up to the GTX 650, a very quiet fanned card wouldn't be heard over your external HDDs.
I didn't know about the AMD cards not downclocking....that's very good to know. The HD 6670 idles at 10W which isn't too bad. The HD 7750 apparently idles at 6W. But, its very likely those numbers are on single display systems. I couldn't find any power consumption figures on the GT 640.
The fanless 520W will work. Given all of the HDDs, you wouldn't hear the equivalent fanned versions. Your actual load power will be in the 200W range...maybe 250W with everything cranked up.
Well, I've only got two hard drives planned so far (the rest are SSDs). They are supposed to be relatively quiet but their placement is certainly not ideal from a noise perspective. You may be right about the noise of the HDDs masking a quiet fanned graphics card. Definitely something to try out.