Home Theater PC - Questions

Hey All!

So I've got this Home Theater PC right now and I find that it is under-performing (especially when attempting to run 1080p high action BluRay movies).

Current Specs:

Motherboard: Elitegroup KN1 SLI Lite (V1.0A)
CPU: AMD Athlon64 X2 3800+ (socket 939)
RAM: 2GB OCZ Platinum EX
HDD: Seagate 250GB SATA2 7200RPM 16MB Cache
WLAN: D-Link DWA-556 Xtreme N PCI-E (300Mbps connection/ Full Bars to a D-Link DIR-655 which acts as a Wifi Access Point only (hooked up to a D-Link DGL-4500).
VGA: Sapphire Radeon HD 5670 512MB or Diamond Radon HD 4350 512MB (Have both at my disposal. First is cooled by an Arctic Cooling cooler which is near silent while the second card is passively cooled). Both cards offer DVI-D, VGA and HDMI.
AUDIO: Currently using an Auzentech X-Fi Prelude 7.1 card hooked up to a Home Theater sound system. The home Theater system does support DolbyTrueHD and DTS HD. Would the Sound devices on either of the GPUs allow for this audio content to simply be streamed to the HomeTheater sound system? Or would they convert/transcode the audio?

System is currently running Windows 7 Home Premium 32-bit (I have MSDN licenses so that's not a problem).


Parts I have laying around:

Motherboard: Gigabyte GA-EX58-Extreme
CPU: Core i7 920 D0
RAM: 6GB Corsair Dominator PC3-12800 (TR3X6G1600C8D)
HDD: 2x Seagate 500GB SATA2 7200RPM 32MB Cache


Now I understand that the components bellow are way overpowered for the task. Problem is that nVIDIA is horrible for driver support and haven't really been supporting any of their nForce products for some time now. In fact they stopped supporting the nForce4 not long after the Core 2 Duo was released. So the fact that nVIDIA is a shitty company leaves my system as is above with subpar HDD performance (nVIDIA doesn't have stable working HDD drivers for Windows Vista/7).

So now the question... is it worth using the Core i7 as an HTPC? Anyone ever use one for such a simplistic task?

Also... would the Radeon HD 5670 offer me better image quality in HD playback than the Radeon HD 4350? Is it worth the added HSF noise (though a silent design by Arctic Cooling)?

Is there an advantage to using pure CPU decode, for HD content, should I go for the Core i7? Would it offer me advantages over DXVA (GPU assisted Decode of HD content)?

Thoughts...


PS. I'll be adding this to the CPU subsection rather than others due to the knowledge from that section and the fact that I am mostly looking at the CPU differences right now.