Splitting HDMI?

I have a pair of Gallo Acoustics SEs and powered subwoofer laying around. I would like to use them as my "computer speakers".  Tidal will be the main music source, but the speakers will also handle gameplay and YouTube videos.

The PC is an original Alienware X51 with an NVidia 1060 graphics card installed. I suppose I could replace that with something more current, but it has been a long time since I have seen a sound card in a PC.

Right now, I am using the only HDMI output on the graphics card to connect to the computer monitor (which has no speakers). The monitor does not have a toslink connection.  Sound is handled by a simple CA-Audio CA3602 2.1 powered speaker system.

Is there a way to also use that one HDMI connection to connect to both the monitor and the stereo gear?  Is there also an USB option for sound?  The Gallo Acoustics only want <100 wpc, so what gear would make sense to connect the PC's audio to (DAC, preamp, amp?)

I understand I could also tap off the PCs audio out (green connection) with a cable that ends in RCA outputs, but I have read that connection is the lowest sound quality.

As always, don't hesitate to offer brand name and model suggestions.
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You’ll get better SQ with a cheap preamp DAC. I DO NOT recommend FOSI because they are bad news but you could try this if you dare:
For $50 you'll get Volume, Tone and a headphone tap.
Just make sure you use Amazon or PayPal protection.
Or try APOS if they ever get their site up.
Cleeds, thank you, I'll look at that.  I wonder what the sound quality of a split HDMI signal is like.

Fuzztone, thank you.  I was looking at the Schitt line of products, but haven't figured out what to put between it and the PC.  Maybe an external sound card with USB to the PC and toslink or coax to the DAC/pre
@kythyn the Alienware X51 has USB ports built-in, so getting an integrated amp with USB audio input is probably your easiest and most cost effective solution. Depending on what your subwoofer is, the integrated amp may need to have an extra set of pre-outs (in addition to the speaker binding posts) so you can connect your subwoofer.

Your suggestion sounds right.  The subwoofer is also from Gallo Acoustics and is powered.  The speakers then connect to the sub.

I'll look for amps with USB input.  Are there are any brands/models you might suggest?