Im having IRQ 17 shared by my both onboard graphics and by onboard Audio.I bought a discrete Radeon 2600XT PCIE,but I was not able to make it work with Vista,no matter what I tried.I even replaced it three times! Is this an IRQ issue?I can not change the IRQ setting through device manager as its grayed out. Can i change the IRQ setting by editing the Registry? I found this in Registry for my audio and video: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\PCI\VEN_1002&DEV_4370&SUBSYS_2A25103C&REV_02\3&18d45aa6&0&A5\Device Parameters\Interrupt Management\Routing Info And HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\PCI\VEN_1002&DEV_5954&SUBSYS_2A24103C&REV_00\4&30239652&0&2808\Device Parameters\Interrupt Management\Routing Info The DWORD value for StaticVector in "Routing Info" is set to 17 for both audio and video. Can I edit this?