HT-R390 vs Realtek Digital output? Y580 and maybe others.

I am connecting my laptop to my surround sound system. At most times, I know HDMI has better audio support than Optical cables, it being newer technology and all. But it also depends on the device and what it supports and outputs.

For my old HP, I use to be able to put sound through the HDMI even without using "projector" mode. It seems that my new laptop, I have to use a dual monitor setup even if a monitor is not connected. This is just HDMI to my surround sound system.

When I select the Realtek as my default, a red light comes out of hte mini optical port which means this is for an optical cable.

My question is, which is better? If HDMI is better, is there a way to just output sound without having to rely on a dual monitor setup?

I'm about to purchase a 30 foot mini optical to optical cable this is what I ask.

EDIT: Sorry... For some reason, I thought HT-R390 was the Intel on board Video/Audio cards. It is actually the name of my surround sound, the computer picks it up due to control support.

What I mean in the OP is Intel Digital Audio (HDMI) vs Realtek Digital Audio (Optical), Y580 and maybe others.

 

So does anyone have any idea and which sends out a better signal?

My receiver is picking up LPCM and all 5 speakers are activate as surround sound. This is through HDMI. I just can't find any information on what our laptops support. HD sound?

I'm about to jump the gun and buy the Mini Optical to Optical cable to try it out. =/

 

Well I guess the Intel Audio drivers through HDMI do support HD sound which Optical cables cannot.