Hi,

I recently put together an HTPC with the following components:

Case: Antec NSK2480 380W M-ATX HTPC Case Black
MB: ASUS P5N7A-VM mATX 9300 LGA775
CPU: Intel Core 2 Duo E7400 2.8GHZ 3MB 1066MHz
RAM: Corsair TWIN2X4096-6400C5 2x2GB DDR2-800
HDD: Western Digital Caviar Green 1TB 32MB Cache SATAII
Tuner: Hauppauge WinTV HVR3000 Triple mode free-to-air
DVD: Sony BR-5100S-0B SATA 2X Blu-ray BD-ROM

HDMI out to Onkyo TX-SR606, and into Sony Bravia LCD.

I've made slow but steady progress in getting everything set up in Windows 7 Media Center.  Have DVB-T Freeview working perfectly (surprisingly straight forward to set up) which is great.  Really impressed with the scope off what can be done with an HTPC these days.  Still plenty to sort out i.e. BSE EPG was working, but then stopped and a couple of ACPI matters, but am sure I can work these out with a bit of time.  However, there is one hardware problem that has me a bit stuck. 

After getting Freeview working, I decided to input my Sky TV (Digital Subscription) into the HTPC via the S-Video input on the HVR-3000.  This was quite simple to set up too, however the reception has some obvious rf-like interference (diagonal fine lines, almost appearing every few seconds for a short while, then going away).  I thought no worries, it must be the cable quality and/or power conditioning, so I upgraded the power box to a surge protection, emi, ground fault detection type, and purchased a more up-market SCART to S-video adaptor and S-Video cable.  Result: no real change to reception interference. 
Below is a list of other steps I've taken:
 - Read common reports on this forum about VGA/Chipset inteference and have moved the PCI tuner card to the end/other slot (only a m-atx board so not many to choose from), no change
 - Tried removing fans, adding fans etc to see if it was an inteference or heat issues from other power drawing components in the box, but no change
 - Tried a more powerful (Enermax) PSU with emi shielded cables etc, no change
 - Tidied up my cabling behind TV, Amp, Sky Box etc (what a mission) to try and isolate interference from other cables as a cause, but still no improvement
 - Quite confident it's not the old Motorola Sky box at fault as the same S-Video output into a Panasonic DVD/HDD Recorder does not show this problem (have tried S-Video direct from Sky Box and via DVD Recorder - no difference).

Now that I've started down this road of having Sky going through the HTPC, I'm determined to try and get it sorted.  I'm not sure whether I'm going to have any luck with this Tuner card for this task, so thought I'd ask for help here.  I understand that the HVR-3000 using software mpeg encoding and am not sure if this could be contributing to the problem.  If so I would be keen to buy another Hauppauge card with hardware mpeg encoding, use that for the S-Video input and continue using the HVR-3000 for Freeview if they co-exist happily.

Do you think an alternative tuner card (i.e. hardware mpeg encoding or perhaps one known for its good quality S-Video input) would offer better results for Sky through S-Video?  If so, which card - HVR-1700 perhaps?  Or would I just have the same result with a new card incurring that same problem?

Hope the above is enough info for those who may be able to offer some insight (just let me know if you need more detail).  Any help would be much appreciated.

Thanks!