I think my HTPC cost me in the $800 - $900 range. I used alot of stuff that I already had on hand, so it is hard to know for sure.
I used
this case in black. It comes with two fans in the back which were a bit too loud for me. No problem, I just modded the wiring on them to run on 7v. Problem fixed. I added two Ultra 80mm fans in front, one of them blows right onto the passive video card in PCI-E slot. The case can hold 92mm fans in front, but I had the 80mm Ultras on hand already. I removed the USB/audio front ports and installed a 64 in 1 card reader. I wanted to use a Zalman 9700 since I had it on hand already, but it didn't fit in the case. Too tall by an 1/8 of an inch!! With this case your CPU cooler cannot stand more than 5.25 inches from top of CPU. I got a Zalman 9500 (approx 5" tall) and set it to silent in BIOS. You can barely hear this PC even when you walk right past it. The only tough spot to work on in this case was where the HDD cage and PSU back up to each other. With the fan in front of the HDD it sticks out of the back of the cage alot. A modular PSU really proved to help here. The rest of the case was a breeze. LOTS of room under mobo for routing wires. The worst thing is the BRIGHT blue power LED on it. Next time I am inside this case I will disconnect it, it is annoying!!
I stuck in a Corsair HX520 PSU...nice and quiet. I used 2 x 1GB Corsair XMS2 DDR2 800 running 1:1 with FSB. Intel E6600 OC'd to 2.57 and undervolted at 1.175. Stays right around 30C for normal use and 39 or so under heavy load, which is irrelevant since the most load it will ever see is about 11% when playing .x264 movie from HDD.
I use one Maxtor 320GB HD and will add more as needed. I made three partitions on the drive...one 10GB partition for OS and apps...one 3GB partition for paging file...and the rest for storage. The case holds six HDD's, but I cut up one of the HDD cages for better air flow, so I can only have three unless I put one in the unused 5.25 bay. Mobo I had on hand was P5B Dlx WiFi. I removed the WiFi card and ran a 25ft cat6 cable to my router.
I got
this video card and so far I am very happy with it. It runs constantly at 40C. Not OCd at all. I don't know really what is an acceptable temp for vid card. I do not yet have a tuner card as I am waiting for a card that can capture in true HD format using QAM tuner.
All of this is attached to my Olevia 237T LCD running at 1360x768 resolution. I used the HDMI for the vid card and disabled the audio for it. I got an Auzen X Plosion for sound and use the SPDIF to my Logitech Z5500 Digital speaker system.
Oh... the price that I estimated did not include the LCD or the speakers, just the HTPC itself.