I just received my 8930 and am looking for two front speakers and a sub-woofer. The CPU is the i7-8700 and the graphics card is the GeForce GTX 1050 Ti (I'm not a PC gamer). I have a pair of Logitech Z623s but these aren't working properly. There is only one RCA cable that connects to the speakers via the sub-woofer, if I plug it into the green port on the 8930 I get nasty feedback. The 8930 documentation says the green jack is the front L/R surround line-out port (#16 on the Quick Start guide) and the port two away from it (#18) is for the Center/Subwoofer LFE surround port. It would seem I need to wire this like a traditional stereo receiver setup as opposed to using only one cable into the sub-woofer with speakers attached to the sub-woofer. I used these speakers with my old Alienware Aurora R4 (bought in 2011) and they worked fine. Does anyone have speaker recommendations for the 8930?
I think that your existing speaker should work and that you don't need new speakers. I think the problem is the way you are connecting your speakers to the computer. I looked at the Logitech documentation and it seems to me that the sub-woofer should be connected to computer's Center/subwoofer LFE surround port (orange port on the XPS 8910). (I am looking at the XPS 8910 Setup and Specifications because I could not find the one for the XPS 8930 online.) To make this connection you need connect the two RCA jacks on the sub-woofer with a 2-channel RCA to 3.5 mm stereo cable apparently not included with the speakers. The left and right speakers should be connected to the sub-woofer and the computer should be connected to the sub-woofer via either the Front L/R surround line-out port (green port) or the Rear L/R surround port (black port). So there are two connections from the computer to the sub-woofer. Finally, you need to go to Control Panel / Sound and under the Playback tab select Speaker/Headphones and click Configure (at the bottom) and then select 5.1 Surround and go through the rest of the speaker setup in Windows. Hope this helps.