IBM has hit what sounds like serious trouble with the microcode for the top-end Model 3 of its forthcoming 3990 disk controller, and as a result has had to delay delivery of the 3990-3, which was due in August, until at least the first half of 1989 and possibly later. The models 1 and 2 will be available as planned in August, but only the Model 3 can accomodate the 4.5 Mbyte-per second channels (CI No 758). The Model 1 is a straight successor to the 3880-3 and 23 and the 2 is a dual processor supporting four separate channel paths to disk. Users can take Model 3s in August, but they will function just like Model 2s, with no cache; the 32Mb to 256Mb cache versions will be available in the first half of next year, and Early Support Programme for the Extended Function – the Dual Copy and Disk Fast Write facilities that are the real purpose of buying the Model 3 – will start at around the same time: a date for the basic cache function – but not for Extended Function – will be announced in the third quarter of this year. This major setback, which will also hit users in a hurry to make full use of the ESA release of MVS, does not mean that users cannot take advantage of the faster channels at all, because the 3880 Models 21 and 23 can be upgraded to support 4.5Mbps data rates – but those controllers are right at the end of their lives, and users will not be keen to make major new investments in them. As a mild consolation for those prepared to wait to use faster channels, IBM is offering those who accept a 3990-3 operating as a -2 a 2% discount on on the Model 2 price, and will be billed for the addition of the microcode at either the price of a 3, less the price of a 2 at the time the 3990 was installed; or the price of the 3 less the price of the 2 at the time the cache is installed, whichever is lower. Customers with a Model 3 on order before April 5 can alternat ively switch their order to a 2 and at the same time order its upgrade to a 3. The delays are not likely to worry many 3090-150 or 200 us ers, but will be a significant con cern to users of the three, four, five and six processor models, many of which will no doubt be hoping that one or more of the plug-comp atible manufacturers can come up with a more timely alternative.
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