Hello, it looks like you will need 2 HDMI to DVI cables, 1 OPTICAL cable, 1 COMPOSITE cable, 5 PCA cables, and speaker wire, and a good quality subwoofer speaker cable. You will need to hook up one HDMI to DVI cable from your HD DVR (HDMI)to your 990 DVI in, and also one optical out of your HD DVR to the 990 optical "in". Hook the other HDMI to DVI cable from the 990 DVI OUT to the HDMI IN on your Sony. Plug the the Composite cable from the VIDEO MONITOR OUT on the 990 to the VIDEO INPUT on your Sony. Use the PCA cables to hook the 7125 to the 990 (also use the supplied trigger wire that will be in the 7125 box from the 990 to the 7125). Hook up your speakers making sure the wires are positive to positive, and negative to negative. You don't want them out of phase, as the same with sub. The composite cable is for using the On Screen Programing/setup of your 990. When I had my Sony hooked up, it was "video 1". It may be different on yours. This info should get you going. Good luck ! You should be very pleased with your purchase.(I am). Outlaw Audio makes some high quality cables if you want order from them. I purchased the PCA cables, and they are very well made, and color coded for easy hookup.
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Outlaw 990/7125
LFM-1 EX
LG 47 inch LCD
Oppo 981HD
Cambridge 640c II CD player

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