I used to use a tricked out 8 bit IBM PC XT. The hardest thing about adding devices to the original PC is that it uses 8 bit ISA cards, not the 16 bit ones. It had...
EGA graphics adapter
Adlib sound card
20 megabyte hard card (it's an ISA card with a built in hard drive)
SCSI controller with a 600 mb hard disk and CD ROM drive
768k of RAM
Floppy controller with high density 5.25 and 3.5 inch disk drives
10base2 Ethernet controller
The device drivers to run all that hardware took up almost all the available memory, so it was more of an experiment in how much hardware I could shove in one computer. I pushed it too far when I eventually put a 386 card in there that would have effectively turned the computer into a 386. After installing the card and powering up, the computer beeped SOS a few times and then never turned on again. It killed BOTH the motherboard and the power supply. I tried putting a new power supply in, wouldn't work. I tried putting the old power supply into another XT, it wouldn't work. It completely killed my machine