A friend asked me to try to sell her son's old Commodore 64C computer. I had fun learning a bit about them. She had saved the original boxes, some of the packing material, and much of the manuals, warranty card, and other paper.
The small box on the left is the power supply for the 64C. On the right is a Commodore 1541C disk drive.
The motherboard has the 6581R4 SID sound chip. I used the sample Basic program in chapter 7 of the Commodore 64 Users Guide to test that all three voices in the chip still work.
Here's an overview of the right side of the motherboard ...
... and of the left side.
I tested it using the sample Basic program in the manual.
Here's some more photos of the Commodore 64C and accessories.