[mythtv-users] Capture Card Power Requirements

[David Rees]

On Wed, Aug 19, 2009 at 9:18 AM, James Crow<james at ultratans.com> wrote:
> Short question: Does anyone know what the power requirements for PCI capture
> cards are?

Generally ~10 watts or less.  My old PVR-250s use about 10 watts.

> I have an AMD Athlon 64 x2 3800+ (89W TDP) on an ASUS nForce 4 based
> motherboard. The system has 5 hard drives, two Pinnacle 800i ATSC/QAM tuners
> as well as a PVR-500 tuner. The PSU is an Antec 430 watt with 28A on the
> 3.3V, 36A on 5V, and 26A on 12V.

Hard to imagine that with a 430w good quality PSU like the Antec that
you'd have any problems, even with all the drives you have.

By the time the system starts booting, the drives should be fully spun
up and pulling 10 watts at the most (assuming that they are 7200 rpm
drives).

I'd guess that your system pulls about 200w at the most during bootup.
 You should pick up a Kill-A-Watt and test it - they're useful for
other things, too! :-)

> Everything was working fine until I added a 500GB Seagate drive and the
> PVR-500. Both components were working fine in another system, but I wanted
> to consolidate both my BE machines into a single system. Once I added those
> two components I booted back up and walked out the door for four days. The
> system ran fine and recorded during that period.
>
> When I returned the system started experiencing hard locks quite frequently.
> The system will boot sometimes and others it will hard lock. If the system
> boots all the way the first FE that tries to connect hard locks the BE. I
> first thought that the 12V rail might be overloaded. The Seagate drives need
> 2.8A on 12V so I should need only 15A for all 5 hard drives. That should
> leave plenty left over for the rest of the system.

Sure sounds suspicious, but could be co-incidental.  Why don't you
just pull the drive and tuner card out and see if that helps?

Personally, I'd be more suspicious of flaky memory.  Have you run the
memtest on the system?  See if you can do so, for at least 12 hours,
preferably 24.

Since you also mentioned you have another computer, can you try swapping PSUs?

-Dave