I am about to put together my first HTPC using some components I could not stand to get rid of. Here is what I am planning on using.
Intel I5-750 (One of the best binned chips possible, ran constantly for 3 years @ 3.96 ghz at 1.195 volts)
8gb DDR 1600
EVGA P55 MB
3 TB WD Green Drive
2x Radeon 5770 XFX cards
Corsair 750W PSU
1 TB 7200RPM Hitachi HD
Ok that is all the old components. The rest is new stuff
OCZ Vertex 4 128gb SSD
Hauppauge WinTV-DCR-2650 Dual Tuner Digital CableCARD Receiver
Silverstone GD07 Case
Windows 8 x64
I am looking to watch/record TV seamlessly via both Fios and services such as Netflix. I also intend to use the computer as a media center utilizing the Plex application to steam to other devices. Eventually I would like to incorporate a few more large HDs and run it as a NAS as well. I was also considering adding an emulator, maybe dolphin, to play incorporate some WII games at 1080P.
My questions are as follows. Will the hardware I have support all those tasks? If not what needs to be replaced. Will I need to OC my CPU to accomplish what I want? I am currently running a cooler master 212 and it will not fit in the new case. I need to know if I need to buy a new cooler or if stock will be sufficient. Do you think ill be using the 1TB Hitachi Drive? I am not sure how much space most systems use recording. I don't want to add the drive if all it contributes to the system is increased noise.
You parts are plenty powerful enough to support all of the tasks you've listed. Actually it's a bit too powerful IMO. There's no need to OC... in fact you may even find yourself underclocking if you have heat or fan noise problems.
The Intel stock coolers are hit or miss with regards to noise. It's probably not a bad idea to go with a quiet aftermarket cooler. The Scythe Big Shuriken is a popular one in the HTPC crowd due to it's good performance and quiet operation. Although, Scythe doesn't seem to have coolers on newegg anymore for some reason. You could also consider the Coolermaster Geminii M4 which is of similar design to the Shuriken.
For the hard drive, 7200 drives are definitely more noticeable than 5400 drives when it comes to acoustics. It may not bother you though and some are more quiet than others. From my experience, HD television recordings take up about 8 GB per hour so a 1TB drive will go a long way. It's when you start getting into ripping blu-ray that you really start to eat up HDD space.