EDIT: I made a few changes:
1. re-did some wiring (mainly changing to a ribbon IDE cable so I could fold it)
2. Moved HDD from lowest position to highest position
3. Experimented with some different fan setups (see below pics)
Thought I'd share pics and info on my new system - any comments or suggestions are greatly appreciated! Full specs are in my sig. I had to DIY a fan mount for the Ninja using some "Jewelry & Craft Essentials" 1mm elastic monofilament (found at Wal-Mart). The metal clips Scythe included were just too frustrating to deal with. I also taped off most vent holes in the case using 3M Electrician's Bundling Tape so that all the air would be drawn in through the filter.
New wiring and hdd location:
Ninja fan mount:
I also had an issue trying to soft-mount the case fan using Verax sticks. The mounting holes on the P150 were too big, so the rubber flange kept pulling right through. The solution was to cut a slice of rubber automotive tubing and use that as a washer.
I tried a few things to improve temps. The first thing I did was to move the hdd from the bottom to the top suspension mount. That lowered the drive temp 5deg. right there.
Next I decided to try the Ninja passive. Idle temps were only slightly warmer, but what really surprised me was how little the load temps went up.
Next I tried adding a 92mm intake in the top position while keeping the Ninja passive. The only 92mm I have is a Dynaeon Top Motor that came with a Chenbro Gaming Bomb. This thing is NOT quiet (buzzing) but I was only concerned with temps so it served its purpose. Drive temps lowered about 4-5 degrees, but cpu and mobo were essentially unchanged.
I finally settled on my original setup with the Ninja active and no front intake. Having the second YL on the Ninja is inaudible (to me, at least) and unless I add a second hdd or put in a more restrictive filter I see no need for a front intake at this point.
Below is temp info as reported by Speedfan. I loaded the cpu by running CPUBurn for at least 20min. set to K7 - High priority, then I stopped burning and let it sit for about 30min. to read idle temps. I did my best to "load" the hdd by running HDTach several times, but couldn't really get temps to budge.
ORIGINAL - 1 YL D12SL-12 on Ninja @ 880rpm; 1 on exhaust @ 860rpm:
Passive Ninja and no front intake - exhaust turned up to 1000rpm:
Passive Ninja w/ 92mm intake @ ~1100rpm (as low as it would go!):
Final setup - Like original but exhaust @ 900rpm, Ninja @ 800rpm:
The question is if I should now go passive on the Ninja. My main reason for not doing so was the the rise in load temp for the chipset, not for the cpu. Am I being too cautious?