I finally got 1080p passthrough from my PS3 through the Onkyo 705 receiver to my projector. What a battle. Turned out to be an inferior HDMI cable. I got the cable off of the internet for 99 cents so I should have known better. I found out it was the cable when i directly hooked up the PS3 to the projector. It would work for all resolutions (720p, 1080i for example), but would not sync when 1080p was connected. Then made a trip down merivale road for the 3rd time in the same day and picked up a PS3 HDMI cable for 60.00 gulp!! but it worked.
BTW, ONYKO product support absolutely sucks. 3 hours on the phone with no response. Sent them an email, no response. This will be the last ONYKO product that I buy. The reciever is fantastic but if you run into any issues, you are on your own. Thankfully the people at Bleeker Stereo and TV are themselves amazing and will never leave you hanging. Much thanks to Claude Champagne. He's been my salesman for 10 years now and always has a smile on his face. Very competitive rates and excellent service.