I do own a H67 motherboard and have the same effects with 2 tv-cards as well with 1 NIC
it might rely on energy settings ??!!
especially on tv-card:
signals are lost at first, then the card is AT LEAST deaktivated in devicemanager
then only to be seen with "view disabled devices"
sometimes th "reactivation" of disabled devices are doing immediate "BSOD"
with -my UEFI Bios some remarkabe reboot reactions are the next
EVEN my Realtec 8169 PCI is doing the same in some cases