Thankfully, the some of the 1541's deficiencies were addressed by a thriving aftermarket for acceleration cartridges and other devices, which also often reduced the need to type arcane commands to get the drive to do something. In 1982, a 1541 floppy drive and a C64 could be yours for under $1,000 -- a nice price considering that an Apple II with no floppy drive cost nearly $1,400. Compared to the datasette, the 1541 ran at lightspeed, and games on disks, unlike cartridges, could easily be copied and distributed -- unless they were copy protected (and users quickly found ways around that). The drive turned out to be much more popular than Commodore had expected, and the company was at first unable to match demand, even though the early models suffered from an extraordinarily high rate of failure.
“The Commodore 64... has to be the most overpraised, deceptively advertised, and ‘user-hostile’ machine to appear in years. If you’ve already got one, you may not (yet) realize how thoroughly you’ve been hornswoggled.” -- Jon Freeman in Computer Gaming World, September 1983
Commodore's next trick was a C64 in a briefcase: an AC-powered portable unit called the SX-64, which looked like the popular transportable CP/M computers from Osborne and Kaypro. Released in 1984, the SX-64 has the distinction of being the first full-color transportable computer, though its small 5-inch screen, heavy weight (23 pounds), and lack of focus on serious business software may have contributed to its lackluster sales (the sticker price was relatively competitive at $995). The SX-64 features a built-in 1541 floppy drive and a sturdy handle, which doubles as an adjustable stand. The only feature missing from the SX-64, standard in the C64, is the datasette port.
In 1985, Commodore released the Commodore 128 (C128), which also failed to perform commercially as well as its predecessor. The C128 features 128K of RAM, a MOS 8502 processor clocked at 2MHz, and a Zilog Z80 clocked at 4MHz. It also boasts an updated operating system, Commodore BASIC V7.0, which addressed many of the deficiencies of the earlier C64 version. While the system is almost entirely C64 compatible, it did receive a new, higher-speed, higher-capacity disk drive called the 1571, which is also necessary for CP/M compatibility (CP/M was an optional and underpowered cartridge add-on on the original C64). A sleeker and more professional-looking model, the C128D, was released soon after and features a built-in 1571 and external keyboard. These multiprocessor systems can be switched between three different operational modes -- C128, C64, and CP/M. In short, it's three computers in one, but, unfortunately for Commodore, most gamers were happy enough with the one.
In C128 mode, the computer makes up for most of its older brother’s technical shortcomings -- it has the ability, for instance, to display 80 instead of 40 columns of text on a monitor thanks to 16KB of dedicated video RAM (64K of VRAM in the 128D). These enhancements, along with a new numeric keypad, make it far more useful for business and productivity applications. Unfortunately, few games were ever developed specifically for the C128, though it was highly useful for running an enhanced version of GEOS, a Mac–like graphical operating system originally released in 1986 by Berkeley Softworks.
The CP/M mode suffers from occasional sluggishness, but makes up for it with versatility; the 1571 can access a variety of otherwise incompatible read/write formats. Unfortunately, by the time the C128 was released, the CP/M operating system was already on its way out as the business operating system of choice, replaced by IBM PCs and "compatibles" running Microsoft’s DOS.
In 1986, Commodore released the C64c, which is basically a C64 system with more modern styling, matching the sleeker lines of the C-128. The C64c was bundled with its own version of the GEOS operating system.