[mythtv-users] New Build

[Eric Yanush]

On 10/03/2010 7:27 PM, Eric Yanush wrote:
> Hi,
>
> I am looking for some insight into my new system build. I was
> originally planning a new backend only system, but have decided to go
> with a combined fe/be.
> I was originally looking at using a athlon II x2 240, but now that I
> have decided to go with a combined fe/be I have completely revised my plan:
>
> Antec NSK2480 case with 380W earthwatts psu
> Intel Core I3-530 @ 2.9ghz
> Scythe Ninja Mini CPU cooler
> 2gb DDR3 Ram
> Nvidia gt220
> WD Caviar Green 1tb HD
> Smaller drive for OS/DB
>
> I was also looking at the gigabyte GA-H55M-UDH2 motherboard, which
> happens to be a shell shocker at newegg today!

Okay, there are a few questions that need to be answered:

Are you doing SD or HD?

If SD, that machine is specced WAY above what you need (My Backend, 
formerly combined backend/frontend 'til the graphics card died, is a 
Sempron 1600+ (That's AMD Athlon, single core, x86) with a GeForce 
FX5200 graphics card, and commflagging is done at ~realtime (if not 
faster)).

If you're doing HD, it's probably still a little high, but you will 
probably want more hard-drive space quickly.

> I will be utilizing IPTV streams from my isp, (similar to verizon
> fios or att uverse) which will be captured via ethernet. Right now I
> will have to capture devices in mythtv, but I plan on adding two more
> in the near future. Besides mythtv fe/be I plan on using this rig as
> a home media file server, running both xbmc and boxee.

This is the kind of system I'm running right now, using Sasktel's Max 
IPTV service (I'm the guy who wrote the guide on the wiki. :) ). I'm 
only using SD (No HDTV), with an original XBox running XBMC as the frontend.

> I did consider using an atom based system as my fe/be but was unsure
> about its ability to do any heavy lifting, ie: comm-flagging.

If commflagging uses VDPAU acceleration (I can't remember if it does or 
not), then a dual-core Atom could commflag 2 recordings at >realtime. If 
not, it'll be a bit slower, though one report listed a single-core atom 
flagging HD recordings at 90% realtime speed (Commflagging while 
recording), so it's not unreasonable to consider that option too.

> I am wondering about the case and its ability to be cooled quietly,
> and if this system would be overkill, particularly the processor?

Given that the only CPU work that will be done is DB and CommFlagging, 
it probably is overload, yes. You could easily scale the whole thing 
back and run from an Acer Aspire Revo (For example), at which point the 
only snag would be hard-drive space. If you bought (or built) a large 
NAS (an old P3 system would be more than fast enough for that), you 
could have a silent combined FE/BE hanging from the VESA mounting 
bracket on your TV (Booting from a CF card, for instance), and the 
(noisy) storage in a closet, or the basement.

That's my $0.02, anyways.
-- 
Robert "Anaerin" Johnston


First I would like to say thanks for the guide, it was awesome. I used it to set up my initial mythtv box using Max.
I originally had a p4 2.8ghz set up with an fx5200, but it just couldn't handle the HD content. 

I am going to use HD content, and that was part of the reason I thought the atom wouldn't be fast enough to deal with 2 let alone 4 simultaneous streams. 
I  do plan on adding atleast 2 more frontends to the mix, (and for those I love the idea of the ION, and I also have an appleTV outfitted with a crystal hd card)
and the concern was that the atom would not have enough power to be able to commflagg more than 1 stream and run a frontend possibly watching live tv at the same time, let alone 2 more streams,
as I was under the impression that myth could not utilize VDPAU to commflag, although that would be awesome:)

As far as HD space, how far will the 1tb drive get me, is there a sort of average per hour size?

The only other reason that I was leaning towards the I3 based setup, was expandability. In the future I could get a faster lga1156 processor and possible expand the life of the machine.

The idea of mounting the Revo to the back of the tv. is an awesome idea, I am just not sure about the idea of having to run a seperate machine for storage. I am trying to design this system with energy efficiency in mind, and have found a few articles that show that the clarkdale series chips can have a system idle draw under 25W!! Plus I seem to be seeing that the core I3-530 is quite a cool running chip, hence the scythe ninja mini, as in the nsk2480 the two 120mm case fans are right beside the processor socket, and the processor could then be passively cooled. However I do imagine an atom chip could be passively cooled without the fans in the case. 

So essentially my only holdbacks from an atom based frontend is the expandability factor, being able to add more fronends in the future, and having it handle the full workload, and being able to future-proof this system somewhat, by being able to replace the processor, and having the extra expansion slots, as most micro ATX LGA1156 boards have atleast one pci express slot and one legacy pci slot, (most having two pci-e and one pci) vs. the atom platform having only the one pci-e slot.

The only other issue I see with either a micro ATX atom board or a Revo is the fact that to expand to four streams, I need atleast TWO ethernet interfaces, and either a third or a wireless card for internet access....

Is there anyone out there that has an I3 or I5  based system that could provide me with feedback??

And Since you seem to be the foremost expert on the Max/Mythtv setup, have you found a way to get the channels like Spike and Peachtree to playback correctly?

Thanks,

Eric 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mythtv.org/pipermail/mythtv-users/attachments/20100311/81f50951/attachment.htm>