seems it does not
after some experiments we find that Dialogic card that does not reqire IRQ works in x8 or x16 slots, but card who requires IRQ does not work (see http://communities.intel.com/message/126713 )
as we have 3 Dialogc cards:one Dialogic D600 (does not require IRQ) and 2 Dialogic DISI32(requires IRQ) we can't make all three cards working on system with DP55KG
as humor is these cards being x1 requires 25W power from the PCIe slot and x1 slot gives only 10W ( http://www.dialogic.com/support/helpweb/helpweb.aspx/990/power_budgeting_jumper_settings_for_pci_express_boards/JCT )... so cards should be installed to x4 or x8 or x16 slots....but as seems x8/x16 on this DP55KG are designed for video and we have a problems....
Also, BIOS on DP55KG has no feature to disable auto resource assign to additoonal PCI/PCIe cards
seems we have to find another motherboard(will it Intel I don't know now) with 3 PCIx slots more then x1 .... the question is how to know this new card will sure work with our dialogc stuff