[mythtv-users] PVR Hardware
James O. Rose, III
james at StubbornRoses.com
Thu May 5 23:01:12 UTC 2005
My delay fixation stems from trying to get CCTV working reasonably with
PVR350s. Even though Hauppauge advertised the suckers as real-time, they
weren't (with windows or Linux). Strange since the conextant chip spec sheet
shows they can be real-time. I suppose I should let this go. I was thinking
this would be really, really annoying for channel surfing, but I forgot to
consider that you use the guide for that now =)
regarding cost on minipcs, I was considering a used 800-1000 MHz Pentium/AMD
or Celery in a SFF case, not necessarily a new via epia.
Agreed it would suck if I lost my network, but if that happens then doesn't
the whole frontend go to heck anyhow? I was still planning on leaving the
RG59 cable connected to the TV for backup...
Does see any benefit to going to GigE? Myself, I've sent 4 MPEG2 streams at
once over 100baseT and SMB w/o any noticable delay for storage, but live
viewing might be another story. I was really considering doing this anyhow
just to make my NFS/SMBed home directories faster.
Will take your (and everone elses) advice and go the ivtv route and stop
worrying about the delay I guess.
Regarding XBOX/PC, the comments seem divided, may just go with a PC so I don't
have to deal with all of the modding, and strange distros.
Thanks for all the advice,
James
On Thursday 05 May 2005 05:13 pm, Gavin Haslett wrote:
> Maybe I'm sort of missing the point here, but why so stressed about the
> delay from live TV? Honestly, my wife and kids use my Myth box and the only
> time they even notice the delay (that they've mentioned) is when changing
> channels. This causes a 3 second delay or thereabouts while live TV is
> cached before the channel "changes". Of course, I know the channel has
> already changed... but that's a detail you live with on any PVR, be it
> Myth, TIVO or any of the "pretenders to the throne". My wife and kids seem
> quite happy to deal with the slight delay for the sake of pausing and
> rewinding live TV.
>
> My setup is a satellite box attached to my Mythbox through an S-Video
> connection for video input to a PVR-250 card. Channel changing is done
> through a serial cable to the back of the satellite box. I use the guide
> built into Myth now instead of the one on the satellite box... in fact
> everything's done through Myth now so I find the delay is such a non-issue.
>
> Catpure Cards: BTTV *might* result in slightly less delay on live TV if you
> recode Myth to override the 3 second built-in delay. May or may not be
> worth it as in the event your machine gets pegged on the CPU or you have a
> glitch on your disk subsystem, you're more likely to get a glitch in your
> TV viewing. Not perfect. Also, BTTV just sends raw frames down the PCI
> bus... which dependent upon other cards in your system may actually
> saturate the PCI bus during high traffic loads. The advantage of capture
> cards like the Hauppauge is that they send only MPEG2 data (pre-compressed)
> down the PCI bus, therefore saving data bandwidth. My first ever Myth-type
> box used a BTTV card... it sucked because (as I later ascertained) I had a
> badly behaved bus-mastering gigabit Ethernet NIC in another slot that was
> causing latency to other cards on the bus. Now I use a PVR-250 and have
> been very happy with the results. I do have some apparent traffic problems,
> but I attribute them more to my disk subsystem which is rather slow than I
> do the card. 3 BTTV cards on the same bus might be a problem... I'd get
> onto doing some mathematics on raw frame speeds down the PCI bus.
>
> Basically, as far as the frontend, you can get your technical requirements
> (fanless, quiet, flash hard disk), but not for less than $200! Even fanless
> and quiet with a hard drive is going to cost you more than that
> realistically. Be realistic about your requirements. Myself, my frontend is
> also my backend... but when I get around to doing a dedicated frontend I'm
> going to spend a few more bucks and get quality and quiet hardware.
>
> Hmm... for a frontend you perhaps might want to consider a modified XBox
> (chintzy solution IMO), or a fanless machine using PXE boot to your
> backend. Works great, but boy, if you lose your network connection...
>
>
> -----Original Message-----
> From: mythtv-users-bounces at mythtv.org on behalf of James Rose
> Sent: Thu 5/5/2005 3:35 PM
> To: mythtv-users at mythtv.org
> Cc:
> Subject: [mythtv-users] PVR Hardware
>
>
>
> This may have been answered many times already, but searching the lists
> (and google) didn't seem to help too much.
>
> I'm wanting to build a distributed myth setup (ie one mythbackend and two
> mythfrontends), and I'm wondering:
>
> 1) What is the best recording card to use? I've got lots of experience
> with Hauppauge PVR-350s (I built a 4 channel recorder..w/o myth), but I
> find the delay completely unacceptable for live tv. I haven't played with
> IVTV since version 1.9, so maybe this is fixed (seems to be a hardware
> issue though). Acceptable delay to me is <1 second. I'm willing to trade
> quality for speed here since I'm recording analog cable to begin with. My
> only other requirement is that it does hardware recording, since this box
> is also my web/mail server (machine is a 2.8GHZ AMD with 1GB RAM, and
> 400GB IDE with RAID6/LVM on Debian Sarge). In addition, I plan on having 3
> recording cards in the box. Are the BTTV devices in general faster than
> IVTV? Can all this even be accomplished at this point in time?
>
> 2) What's the best compromise for mythfronend systems. I've read a lot of
> mixed reviews on using xboxes/ps2s. I'm wanting something really cheap
> (around $200/box), and extremely quiet. I'd like fanless, and may skip
> the hard drive and go with flash memory.
>
> MTIA,
>
> James
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
More information about the mythtv-users
mailing list