PCIe Device and Cold Boot

After de-capacitor-tating my previous DVB-S2 card while cleaning out the heat sink on my CPU I had to buy a new PCIe Satellite card for my mythtv box (DVBSky S952 v3).

Needless to say yet again I’ve managed to buy some relatively new hardware and had fun getting all the drivers to play nicely with my other TV cards.  I thought it was all sorted – that was until the next day when I found out nothing had recorded.  Turns out from a cold boot (pc shuts-down when not in use and starts up just before a recording) the PCIe card doesn’t get picked up – reboot and its found.  Great…

It seems its either a bug in my BIOS or a slow initialising card (both are buggy in my opinion – the BIOS should ensure all hardware is running and the card shouldn’t be so damn slow).  After playing round with the BIOS settings I’ve found a fix/workaround.  In my BIOS I can change the graphics card initialization order – it seems if I tell it to try start a graphics card in the PCIe X1 slot first (which is actually the tv card) – the card gets picked up.

Hopefully my next motherboard will be more tolerant.


Looks like I jumped the gun.  This does work for a cold boot if powered back on within a few minutes.  Leave it a bit longer and it still fails to pick up the card

A bit of poking around and I’ve found a fix – force the PCIe bridge to rescan (0n 00:04 for me).  lspci might help you identify yours

echo 1 > /sys/bus/pci/devices/0000\:00\:04.0/rescan

Hopefully this time I should have all my TV cards from a cold boot.

June 1, 2015 · robert · Comments Closed
Posted in: bugs, Hardware