[mythtv-users] CPU for combo frontend/backed box

[Johnny]

> I'm trying to decide between a 65W 3.0GHz dual-core CPU (Intel Core 2 Duo
> E8400 Wolfdale 3.0GHz) or a 95W 2.33GHz quad-core CPU (Intel Core 2 Quad
> Q8200 2.33GHz). I'd like the performance of the quad-core CPU, but if the
> dual-core would work fine I'd rather go with that and have less heat in the
> HTPC-style case.

You don't need much of a CPU. Recording requires very little CPU. You
could use almost any CPU available today for that. Also for playback
of most formats you would be using in mythtv you can use Nvidia's new
hardware accelerated rendering (known as VDPAU). VDPAU isn't
officially supported until mythtv .22 comes out in the next month or
so. VDPAU will accelerate MPEG2 and H.264, and also provides some
excellent hardware deinterlacers. With VDPAU you can playback HD H.264
video even with an Atom processor. However, if you were only going to
use the CPU for playback, then any dual core at 3.0 GHz should be
fine. Some of the most CPU intensive recordings to playback come from
the HD-PVR which records component inputs and encodes it to H.264 at
HD resolutions. However, because of some technical detail decoding
these can't be divided up among multiple cores. So you really want to
get fewer faster cores over more slower cores (for this purpose). But
assuming you use VDPAU, which I strongly recommend, this is a moot
point. So for recording and playback the dual core would sufficient
and you can even go way way less powerful if you like.

The other duties that the CPU handles that can be CPU intensive are
commercial flagging and transcoding. Depending on how many shows you
intend to record simultaneously and how many you want to commercial
flagged in real time, you may want some more power for this. But the
dual core intel should be plenty of power for these duties for all but
the most heavy mythtv users.

> Case: SILVERSTONE LC10B-E ATX
> MB: Gigabyte GA-E7AUM-DS2H
> RAM: CORSAIR 4GB (2 x 2GB) DDR2 800
> CPU cooler: Scythe Big Shuriken
> Case fan: Nexus SP802512H-03PWM
> HD: WD Caviar Green 1TB
> DVD: LG GH22LS30
> PSU: Enermax Modu82+ 625W
> Tuner: Haven't decided yet

I assume you are going to use the onboard nvidia 9400 via HDMI for
playback. If so you may not be able to use the highest end VDPAU
deinterlacer (Advanced 2x) on HD material. There others like Temporal
2x that work nearly as well so you may just have to try and see what
you think. Otherwise if you care about that you may want to look at a
discrete fanless card like the 8500, 8600, 9500, or up. Also it is
often highly recommended to have your system partition on a different
disk than the disk your recordings are on. While you are recording and
comm-flagging there will be a lot of database activity, so recording
to the same disk that the database is on can cause a lot of thrashing
and in heavy usage situations can lead to other problems. I would try
and get another smaller disk for you OS to go on. I keep my OS and
mythvideo stuff on one disk and all my recordings on the other disks.