I've always been a bit of a computer audio nerd. Here's what I use.
Gaming PC - onboard Realtek ALC1220 to Swan M50W 2.1 speakers. These are probably the nicest sounding PC speakers I've ever heard, with lots of detail in the higher frequencies (yet not bright or fatiguing), and a nice, clean low-end. The sub is definitely capable for a 6.5" unit - the lower frequencies in movies and games absolutely shake my chair, yet it never overpowers the satellites or sounds boomy. As with most PC speakers, this is definitely a near field system. It sounds absolutely wonderful when you're sitting in front of it, but bass drops off quite quickly as you move away. One minor complaint: as the satellite drivers are only 3", certain midrange frequencies aren't quite as full-sounding as you'd get from a proper hi-fi with larger main speakers, but that's to be expected from any sub/satellite based system.
Office/bedroom PC - onboard Realtek ALC898 to Swan M10 2.1 speakers. Very stylish set. Good range and remarkably flat output for a $100 2.1 setup. However, the silk dome tweeters are definitely subdued--you might even think the high-end response is somewhat "boring" compared to many other PC speakers, especially for movies and gaming. For most kinds of music, however, I actually prefer this!
Retrogaming machines - They are all plugged into an older Sony stereo receiver from 1992, powering Klipsch RB61-II bookshelf speakers. You can buy these older receivers for peanuts at thrift stores and garage sales, yet they have far more amplifier power than PC/multimedia sets. Hooked up to larger bookshelves like the Klipsch RB61-IIs, you can tell right away that you're listening to a larger system - it has a much easier time filling the room with sound than the M50Ws, and with none of the bass dropoff as you move away from the system. One word of advice: if you're not going to be using a subwoofer, avoid 5.1 surround receivers. The plain old stereo amps seem to pump a much fuller sound--with lots more bass content--through your speakers than 5.1 receivers, even if you configure the 5.1 receiver for full range stereo output.
486 PC - Creative Inspire P7800 7.1 speakers. I only have two of the satellites plugged in, so it's running as a 2.1 set. Typical cheap mid-2000s multimedia surround set, but the AWE64 doesn't exactly output the cleanest audio, so I guess it's a match made in heaven. And actually, the somewhat bright satellites and somewhat boomy sub act as a natural equalizer of sorts to the AWE64's output, and they manage to sound quite great together. I certainly can't get this set sounding as good with the much flatter output of any modern source!
HTPC in the living room: Optical out to a DAC connected to a late 70s Marantz receiver, driving a pair of Infinity Kappa 6 floor standers and a passive Dahlquist DQ-1W 13" sealed subwoofer. I was lucky enough to find the Dahlquist and its passive crossover module at a yard sale a few years ago. This system sounds absolutely incredible and especially shines with older analog sources.
HTPC in the basement: HDMI out to Denon AVR X7200WA receiver. Using an external Emotiva XPA-3 to drive the three Philharmonic Audio BMRs up front, and the Denon's built in amps to drive the four PA AA-II surrounds. Subwoofers are a pair of SVS PC13-Ultras. DOS games sound fantastic on this rig, and that's all I have to say about that. 😜
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