Impressive. Most impressive.
I did basically the same thing, PC output via HDMI to TV, toslink SPDIF output to DAC section of a modded Cambridge 740C. I did not set the output level to THX STD so peaks were maybe 90dB instead of 105dB. I would have been a real hoot at 105dB, but my wife would not have appreciated it at this time of night.
Scotty