The IBM 4300 series are mid-range systems compatible with System/370 that were sold from 1979 through 1992. They featured modest electrical and cooling requirements, and thus did not require a data center environment. They had a disruptive effect on the market, allowing customers to provide internal IBM computing services at a cost point lower than commercial time-sharing services. All 4300 processors used a 3278-2A, 3279-C or 3205 display console rather than a 3210 or 3215 keyboard/printer console. Models Each model - 4331, 4341, 4361, and 4381 - had various sub-models, such as the 4341 model 1 (or 4341-1) and 4341 model 2 (4341-2). The 4381-13 through 4381-24 (announced in 1987) were entry-level machines for the 370-XA architecture. They were positioned between the IBM 9370 and IBM 3090 in performance at the time of announcement. The 4381-3, 4381-14, 4381-24 and 4381-92 are dual-CPU models. Other models included 1, 2, 11, 12, 13, 21, 22, 23, 90 and 91. IBM 4321 The IBM 4321 was announced on 18 November 1981. IBM 4331 The IBM 4331 (and the 4341) were announced on 30 January 1979. It came with an integrated adapter that permitted attaching up to 16 of two newly introduced direct-access storage devices (DASD): The IBM 3310, described as having "a storage capacity of 64.5 million characters", was to be used with "Storage disks .. sealed to reduce the possibility of damage, loss, misuse or contamination". The IBM 3370 with up to 571 million characters could also be used with an IBM 4341. The 4331 was withdrawn on 18 November 1981. IBM 4341 The IBM 4341 (and the 4331) were announced on 30 January 1979. Like the 4331, it came with an integrated adapter that permitted attaching up to 16 of the newly introduced IBM 3370 DASD. The 4341 did not support the much lower capacity IBM 3310. The 4341 Introduced the Extended Control Program Support:VM (ECPS:VM) and Extended Control Program Support:VS1 (ECPS:VS1) features. The 4341-2 introduced the Extended Control Program Support (ECPS:MVS) option, a subset of System/370 extended facility. On 20 October 1982, IBM announced a new entry-level 4341 model, Model Group 9 and a new top-of-the-line 4341, Model Group 12. Model Group 12 included the Dual Address Space (DAS) facility. The 4341 was withdrawn on 11 February 1986. IBM 4361 The IBM 4361 Model Groups 4 & 5 were announced on 15 September 1983. Model Group 3 was announced the