Optical 5.1 requires Dolby digital live or DTS live which enables on the fly encoding so that 5.1 can be sent. Otherwise its limited to 2 channels with PCM.
Even if that works one thing to be aware of is that while many sound cards do support this (soundblaster Z, soundblaster xfi, all the Xonar cards and most cmedia cards) some of them introduce upwards of 100ms of latency to do it, so they can be really bad for gaming.
Conversely using HDMI and splitting the sound and video there can allow 5.1 with PCM or DD or DTS but at the same time it will add latency to the video , typically at least 16ms depending on your receiver. So its a tough trade off choosing between HDMI and optical output for 5.1 with receiver driven speakers for gamers at least.
There shouldn't be any added latency through the use of HDMI from your PC any more than you'd get from a PS4 hooked up to the same TV and through the same receiver.
i wish i hadnt read that. thanks for telling me a truth that i hadnt thought of though.Its because with HDMI you are putting both the audio and video through the AV receiver, which does add latency in the grand majority of receivers. They are designed for movies not really gaming unfortunately.
Its because with HDMI you are putting both the audio and video through the AV receiver, which does add latency in the grand majority of receivers. They are designed for movies not really gaming unfortunately.
Of course if you are watching a DD or DTS source then there is no encoding delay. So the impact really depends on your source material. Are we talking about gaming, movies or music?