You may want to try the device you want in place of the display@0 I have in the following it seems to be close to what you need to get.
CODE
MacUser2525$ ioreg -p IODeviceTree -n display@0 -r
+-o display@0 <class IOPCIDevice, registered, matched, active, busy 0, retain 15>
| {
| "IOPCIResourced" = Yes
| "IOInterruptControllers" = ("io-apic-0","IOPCIMessagedInterruptController")
| "IOName" = "display"
| "subsystem-id" = <10000000>
| "IODeviceMemory" = (({"address"=18446744073541779456,"length"=16777216}),({"address"=18446744$
| "class-code" = <00000300>
| "revision-id" = <a2000000>
| "IOChildIndex" = 1
| "assigned-addresses" = <1000018200000000000000f60000000000000001140001c200000000000000e000000$
| "model" = <"NVIDIA GeForce 8800 GT">
| "AAPL01,blackscreen-preferences" = <00000008>
| "AAPL,iokit-ndrv" = <e0021079>
| "name" = "display"
| "AAPL,backlight-control" = <00000000>
| "subsystem-vendor-id" = <42380000>
| "AAPL00,blackscreen-preferences" = <00000008>
| "AAPL,interrupts" = <1000000007000000>
| "reg" = <0000010000000000000000000000000000000000100001020000000000000000000000000000
0011400$
| "compatible" = <"pci3842,c801","pci10de,611","pciclass,030000">
| "AAPL,aux-power-connected" = <01000000>
| "VRAM,totalsize" = <00000020>
| "AAPL00,Coherency" = <02000000>
| "driver-ist" = <80f1d90a0100000080f1d90a0200000080f1d90a03000000>
| "AAPL,ndrv-interrupt-set" = "IONDRVInterruptSet is not serializable"
| "rom-revision" = <"3233">
| "NVDA,Features" = <ff024f05>
| "NVCAP" = <05000000000003000c0000000000000b00000000>
| "AAPL,EMC-Display-List" = <03000000000000000000000000000000061000001b920000000000000000000006$
| "NVDA,current-arch" = 146
| "IOPCIExpressLinkCapabilities" = 15618
| "NVDA,gart-width" = 64
| "NVKernelLoaded" = <01000000>
| "AAPL,gray-page" = <01000000>
| "saved-config" = <0b0830024f0500002100ac10a0190003027f90061a0430073000500038040300090008007c2$
| "rm_multiboard_capable" = <01000000>
| "IOPowerManagement" = {"ChildrenPowerState"=2,"CurrentPowerState"=2}
| "AAPL,gart-width" = 64
| "rm_board_number" = <00000000>
| "IOInterruptSpecifiers" = (<1000000007000000>,<0600000000000100>)
| "twinView-driver" = <0040bb1f>
| "IOPMIsPowerManaged" = Yes
| "IOHibernateState" = <00000000>
| "device-id" = <11060000>
| "vendor-id" = <de100000>
| "device_type" = <"NVDA,Parent">
| "AAPL,gray-value" = <c38c6400>
| "IOPCIExpressLinkStatus" = 4353
| "AAPL,ndrv-dev" = Yes
| }
|
+-o NVDA,Display-A@0 <class IONDRVDevice, registered, matched, active, busy 0, retain 10>
+-o NVDA,Display-B@1 <class IONDRVDevice, registered, matched, active, busy 0, retain 9>