Configuring 2.1 for downmixing 5.1

[RBX]

I have a 5.1 set, but my desktop supports only 2.0, so I have connected Front L+R, but it's somehow working as 2.1.

My media player supports following speaker configurations
*i.imgur.com/0nDzAje.png


And the selected settings seems to be producing best output. Please provide info on what do these mean when output consists of stereo/5.1 audio.

Also, does the following setting override the former?
*i.imgur.com/WckfuAu.png

Edit:
I had read a lot on how to connect 5.1 speakers to PC, but hadn't found a thing. They all said that a card would need to be added. On a whim I downloaded some audio drivers, and now my Jack information looks like this, and all speakers work.

*i.imgur.com/gbXnPmp.png

Edit:
The problem now is that when I select output speakers as 5.1 (or anything other) in media player (Potplayer), only Front speakers work, but when I select 'Speaker Fill' from device's settings, and set output speakers as Dolby Surround in media player, they all work.
Each of them used to work with my laptop (which has 5.1 capability) even with stereo audio.
Is there any setting that allows playback of 5.1 when 5.1 audio is present but upmixes to 5.1 when stereo audio is present?

 

[Minion]

Why don't you get cheap sound card like asus xonar DG.

 

[whitestar_999]

First of all no laptop has "true 5.1 output" unless it has a spdif port(a rarity in laptops).Second,dolby pro logic is just virtual surround sound.When you select 5.1 speakers in media player but the source is only 2.0 stereo then for all speakers to work either your media player or your audio driver should do the upmixing of 2.0 to 5.1.It seems like some setting clash & only way to figure out is by experimenting.If spending ~2k is not an issue get asus xonar DGX which is pci-e(Xonar DG needs pci slot which is old & rarely found in new/latest mobos) which will provide better audio quality as well as lesser configuration hassles.

 

[RBX]

Why don't you get cheap sound card like asus xonar DG.

First of all no laptop has "true 5.1 output" unless it has a spdif port(a rarity in laptops).Second,dolby pro logic is just virtual surround sound.When you select 5.1 speakers in media player but the source is only 2.0 stereo then for all speakers to work either your media player or your audio driver should do the upmixing of 2.0 to 5.1.It seems like some setting clash & only way to figure out is by experimenting.If spending ~2k is not an issue get asus xonar DGX which is pci-e(Xonar DG needs pci slot which is old & rarely found in new/latest mobos) which will provide better audio quality as well as lesser configuration hassles.

I don't have the need of 5.1 audio, I just had speakers lying around, and if I can make the most out of them, then I'd be happy.


And my laptop seems to have S/PDIF capability.
*i.imgur.com/Gvw5hKy.png

 

[whitestar_999]

That is what i am talking about.Unless you use an adapter(hard to find & costly too) it is not possible to get true 5.1 from laptop,only very costly laptops have spdif port with no need for any adapter.You can get virtual 5.1 from laptop by using 3 audio out ports which is what your laptop was/is doing.