can be upgraded by adding the additional DRAM chips and some resistors for the control lines. The MEGA 1 mainboards had a redesigned memory chip area and could not be upgraded in this way as there are only places for the 1 MByte DRAM chips. 520STE and 1040STE a 520STFM/1040STFM with enhanced sound, a BLiTTER chip, and a 4096-color palette, in the older 1040-style all-in-one case Mega STE same hardware as 1040STE except for a faster 16 MHz processor with 16K cache, an onboard SCSI controller, additional faster RS232 port, VME expansion port, in an ST gray version of the TT case STacy a portable (but definitely not laptop) version of the ST with the complete ST keyboard, an LCD screen simulating 640x400 hi-res, and a mini-trackball intended mostly for travellers and musicians because of the backlit screen and its built-in midi ports. Originally designed to operate on 12 standard C cell flashlight batteries for portability, when Atari finally realized how quickly the machine would use up a set of batteries (especially when rechargeable batteries of the time supplied insufficient power compared to the intended alkalines), they simply glued the lid of the battery compartment shut. ST BOOK a later portable ST, more portable than the STacy, but sacrificing several features in order to achieve this, notably the backlight and internal floppy disk drive. Files were meant to be stored on a small amount (one megabyte) of internal flash memory 'on the road' and transferred using serial or parallel links, memory flashcards or external (and externally powered) floppy disk to a desktop ST once back indoors. The screen is highly reflective for the time, but still hard to use indoors or in low light, it is fixed to the 640 × 400 1-bit mono mode, and no external video port was provided. Despite its limitations, it gained some popularity, particularly amongst musicians. Unreleased The 130ST was intended to be a 128 KB variant. It was announced at the 1985 CES alongside the 520ST but never produced. The 4160STE was a 1040STE, but with 4 MB of RAM. A small quantity of development units were produced, but the system was never officially released. Atari did produce a quantity of 4160STE metallic case badges which found their way to dealers, so it's not uncommon to find one attached to systems which were originally 520/1040STE. No such labels were produced for the base