: Using a HTPC for PVR & PC use simultaneously


john_ertw
2008-02-07, 09:13 PM
I’ve been doing a fair amount of reading about HTPC’s over the past few weeks as I am thinking about utilizing one to act as a PVR. The idea I have in my head is to configure a single PC which will reside in my study and be connected to the HDTV in the family room as well as a computer monitor in the study. This computer will be used as both a PVR and a PC. There will be times where it is only used as a PVR or only as a computer, but there will also be times when the computer will be used while someone is watching TV or a show is being captured. I have yet to come across any information about using a computer in this fashion and I’m not sure if the technology available is fast enough to cope with both tasks simultaneously.

As for details of the HTPC tasks, I want to use it as a PVR for HD and SD OTA as well as for analog cable. The computer usage will almost certainly be limited to web surfing and word processing especially while the PVR is in use so the additional strain on the computer's resources should not be too high. I have no plans to purchase a HD-DVD or Blu-ray drive right now, but purchasing hardware that can cope with their demands would be nice.

Is this setup possible for a reasonable price ($500 - $1000)?

As for computer parts, do I need 2 video cards (one for the TV and one for the monitor)? I assume I will definitely want a video card that can handle the video processing for the TV connection to offload the work from the processor. What speed processor and how much RAM would be recommended? I am also thinking that 2 hard drives would be a good idea so that the PVR drive has nothing to do with the drive the computer uses for programs. I know I can get ATSC OTA capture cards, but is there anything available that will capture both ATSC OTA as well as analog cable?

jvincent
2008-02-07, 09:52 PM
What you are talking about doing is indeed possible. You just need to make sure you have enough CPU power and RAM. Faster is always better in this case.

I believe all of the OTA cards will also handle analog cable but you need one with two inputs. I haven't kept up with tuner cards but I'd look at the Hauppage line.

You should only need one video card since pretty much all of them support two displays.

Fair warning though, multi-monitor setups can be tricky to setup / manage.

PPL4GOLF
2008-02-07, 11:58 PM
That's pretty much the beauty about HTPCs...I am watching OTA HD while I make this post...CPU is a only a stock speed A64 3800+ x2

Since moving to a dual core, even a low end one like 3800+ x2, there is no issue with video stutter doing all kinds of other things simultaneously.

Silent Recording is non issue because it doesn't need much CPU juice...ATSC I'm just recording the transport stream directly...NTSC the TV capture card does the hardware encoding for you. So make sure you're getting a hybrid card that does both (many may not do both at the same time but hybrid cards can do both)

rfielder
2008-02-08, 09:03 AM
When my PVR PC had an ATI All In Wonder 9600 XT, doing anything else on the computer could impact on TV capture. That was SD from cable. As a result, the PVR PC was dedicated to that function alone.

Since upgrading to a PCI TV Wonder 650, that issue has dissapeared. This is because the encoding is done on the TV card, while it was done by the PC with the AIW card.

I have not tried OTA HD, although the TV Wonder 650 can do that. Personally, I would be concerned about bandwidth on the buss if I were capturing HD and using the PC for other functions. Should be easy enough to test, just capture an OTA HD broadcast while watching a record show and surfing the internet - do a real world test.

Then again, my computers are all PCI based. With PCI-e, SATA II drives, and a good video card, things could look very nicely.

I have been doing multimonitor setups for many years. They are usually no problem, although sometimes the drivers can make things interesting. At one point, I had four ports and three active monitors on a PC at work.

My favourite video cards for this sort of thing have always been Matrox units, and I still love the P750. However, Matrox has been left behind by HD video. Currently, both HTPC setups I have use Visiontek HD2600 AGP video cards, which are working well. Both are dual monitor, but neither have had a second monitor attached, so I don't know how well they work in that configuration.

john_ertw
2008-02-08, 05:38 PM
Thanks for all the great responses so far.

From my understanding, OTA (ATSC) is MPEG2 and only has to be recorded to disk during capture without any encoding (processing). From PPL4GOLF and rfielder's remarks it looks like capturing analog cable (NTSC) requires encoding (processing) of the signal as well as recording to disk. What format does analog cable come in at and to what format is encoded to before recording on disk? What do I need to look for in a video capture device to ensure it can do this encoding in hardware?

From my research on video cards, it seems that the current tv out cards focus on Bluray and HD-DVD decoding in hardware, but they do not necessarily do MPEG2 decoding in hardware. Is this correct? Are there any cards that do handle this in hardware?

With respect to the encoded cable video, what feature does a video card need to decode it in hardware?

In terms of PVR interface from my family room, I want to use a remote control. Can someone point me in the right direction for a remote that will work from a different room than the computer is located? Can a receiver can be wired from my family room to the computer or does the computer have to be in the same room?

jvincent
2008-02-08, 05:52 PM
Analog cable comes in as, well, analog. The capture card samples it and then it is encoded into either MPEG or whatever other formats your card supports. Look for a card with H/W encoding for the most consistent results.

All current video cards also support MPEG decoding in H/W.

PPL4GOLF
2008-02-10, 01:11 PM
The most popular ones are the Hauppauge HVR 1600/1800 and the ATI650 under various brands.

I personally use the Sapphire Theatrix 650 PCI which has ATSC and hardware encoding for Analog (NTSC). I only use it for OTA-HD and it has served me well, very stable using WatchHDTV, the tuner is not as sensitive as the tuner in the LG plasma.

Get one that comes with a remote...you can go wrong with either.

Wayne
2008-02-11, 09:42 PM
You will need the CPU power for playback of HD rather than the recording of either SD or HD. You will likely need an RF remote - they can work without line of sight but I haven't really used them before so I can't help on suggestions.