It is an improved version of the Commodore 64, and it was meant to be backwards-compatible with the older computer, while still providing a number of advanced features close to those of the Amiga.

's Gazette noted that "Sales of the 64 have diminished rapidly, Nintendo has eaten big holes in the market, and the life of the old warhorse computer should somehow be extended."

The final tidbit is that the 64GS will retail in the $300-$350 range when it debuts in November.The Gazette added, "Our sources also report that there is a great deal of infighting at Commodore as to whether the machine should be released.

Estimates as to the actual number of machines found on the open market range from 50 to 2000 units.

[4] As the C65 project was cancelled, the final 8-bit offering from CBM remained the triple-mode, 1–2 MHz, 128 KB (expandable), C64-compatible Commodore 128 of 1985.

According to former Commodore engineer Bill Gardei,[9]The Legend on the PCB was to let others in the organization know [whom] to go to for advice on the chips.

To further increase the bandwidth of the graphics subsystem, the memory is divided into 2× 8-bit wide banks of 64 Kbyte which can be accessed by the CSG-4567 simultaneously.

This provides an effective video-DMA bandwidth of 7.2 MB/s which is the same specification as the original 16-bit Commodore Amiga chipset (OCS/ECS).

In addition to having all of the C64 video modes, the CSG-4567 also supports several new character attributes such as "blink" or "bold" and can display any of the new or old video modes in 80 column or 640 horizontal pixel format, as well as the older 40 column 320 pixel format [6].

On a basic system, it would probably have made more sense to write software which uses less demanding resolutions with fewer bitplanes—partly because this would consume less of the confined RAM space, but also because more bitplanes would demand a higher video DMA bandwidth and consequently slow down the CPU as a result.

Because this makes it harder to derive individual byte and pixel addresses from their position in the XY coordinate frame, the C65 provides a conversion mechanism in hardware called Display Address Translator (DAT).

Further aid to the programmer comes in the form of a bit-blitter, which supports In contrast to previous 8-bit computers from Commodore, the C65 has a complete DOS through which the built-in 3.5-inch floppy disk drive can be controlled.

Since this format was uncommon for the former C64 owners, the C65 retains the serial IEC port for external Commodore disk drives.

[21][22] The third batch followed a few months later and incorporates a few technical updates on the mainboard [reference to be added].