So I finally got my Antec NSK1480 case for my HTPC. I bought it for it's size, looks, and the fact that it at least comes with a half decent PSU. But as it is a slim case, it does make it difficult to keep quiet compared to larger cases. Here are the mods I've made so far to help out with it and the parts I'm currently using...
Pentium M 725 1.6GHz
Samsung 40GB 2.5"
The biggest problem out of the box was the fans. The PSU fan is a slim 80mm high speed fan that clicks a lot. The two side/rear fans are hard-mounted and squeeze in between the side and a ridge. Any clicking or noise from these get amplified through the case. I originally swapped the Antec tri-cool fans for a pair of AC PWM fans. Although this MB doesn't support PWM fans. For some reason these things clicked terribly and with the hard-mounting sounded terrible. The tri-cools on low don't seem to click at all and are slow enough that I've put them back. I removed the front/side fan. That's where all my spare wires are anyways.
The PSU fan was removed and the grill was cut out. I then took an old medium speed ball-bearing Panaflo fan that I had and surrounded it with weather stripping on all sides. The hole in the PSU was larger then the fan and the weather stripping fills in the gap holding it in place. There was some weather stripping on the case around where the old fan was. That got in the way and had to be removed. This fan is much less clicky and runs slower. So everything is looking good here.
For the side/rear fans, the metal ridge was cut off. There's probably room for two fans stacked between the side and the motherboard. Not exactly sure why they put this ridge here in the first place. With that gone (and the rough edge covered by duct tape), I had plenty of room to soft mount the fans. My preferred method of fan mounting was used... Weather stripping around the edges, hair bands to provide the tension and bobby pins to hold the hair bands. Again much better than it was.
Now this is still not silent by any means. The tri-cools even on low are a bit fast and the panflo fan isn't the best either. But it's way better than it was and is inside of cabinet across the room from where we sit and quiet enough that it can't be heard over even quiet scenes when watching stuff. I could go with slower fans. But the video card gets pretty hot as it is. Any slower and I would worry about those temps. I hope to eventually use my Gigabyte 780G motherboard with an AMD 4050e CPU. But that MB is giving me problems and will be sent for some work soon.