New HTPC/Server Build - Recommend Changes!

[StevenBullen]

Approximate Purchase Date: in 2 weeks
Budget Range: Cheaper the better(-ish) I am not made of money lol
System Usage from Most to Least Important:
Streaming to AppleTV 2 XBMC (720P moving to 1080P occasionaly in the future) & TV of course through HDMI
Running two Windows 7 programs all the time the machine is on

Parts Not Required: OS Hard Drive
Preferred Website(s) for Parts: Overclockers UK
Country: UK
Parts Preferences: Below
Overclocking: No
SLI or Crossfire: No
Monitor Resolution: It will be on TV so 1920+
Additional Comments:
I currently have a few internal drives and a few external drives connected to an old server and looking to move it all inside a new htpc/server. So I am looking to spec a new htpc/server and need some recommendations.

Requirements
Storage - 15TB RAID 5 (12TB)
Quieter the better
Lower power consumption the better
Windows 7

This is what I have so far
Case - Lian Li PC-C60B HTPC Case
Motherboard - Asus Z77 Sabertooth Intel Z77 (Socket 1155) DDR3 Motherboard - Possible overkill for an HDMI out and SATA RAID on board
Processor - Intel Core i3-2100 3.10GHz (Sandybridge) Socket LGA1155 Processor
Memory - Not Sure
Power Supply - Corsair 500W - Not sure on exact model
HD x 5 (Storage) - £130 each Seagate Barracuda 3TB 7200RPM SATA 6Gb/s 64MB Cache
SATA Controller Card - Was hoping to use the onboard RAID
Graphics Card - Was hoping to use the onboard HDMI

Any changes you would advise?

 

[StevenBullen]

Ok after some investigation it looks like this motherboard is more than capable of running the RAID configuration and will output to HDMI with no problems. Also it's half the price
MSI Z77A-G43 Intel Z77 (Socket 1155) DDR3 Motherboard

 

[jmsellars1]

Looks OK to me, just make sure the PSU has enough SATA connectors. If you're using onboard graphics too, I'd go for the i3-2105 because it has Intel HD 3000 instead of 2000, it's quite a lot better.