Hi all, I built myself a new PC and decided to use the old hardware for a HTPC.
Current Specs

•  Generic LGA775 motherboard
•  Dual Core E5200 @ 2.5Ghz
•  Nvidia GeForce 7600 GS (Silent) with 256MB dedicated, 767MB shared system memory. This is currently using the Microsoft WDDM driver) and VGA output to the TV.
•  2GB DDR2
•  Windows 7 Home Premium SP1 - Running Windows Media Centre
•  Hauppauge WinTV-HVR-2200 (Dual HD DVB Tuner)
•  160GB 7200 8Mb Seagate sata hard drive (ST3160811AS)
•  1360x768 LCD TV (LC37A53X) I realise this isn't Full-HD, but its adequate for now.

Everything looked good at first but after a while we noticed its not nearly as smooth as the old dedicated freeview receiver I had (homecast ht3000)
Most of the time its watch-able, but it is like the frame-rate is lower than it should be. Fast motion doesn't look good and sometimes It would be as low as maybe 5-10fps. Occasionally the screen will tear so the bottom 1/3 or so is black/deformed. Also changing channels takes a little while to come right.

I imagine its either the video card or the hard drive. I was planning on putting in a second 1TB and setting up the recordings to go there. I assume running the OS and the recordings on different drives will make a huge difference but maybe someone has an opinion on this?

And also I want to put a blu-ray drive in, Any thoughts on the specs with that in mind?

Thanks in advance!