Customers that buy unauthorised 3090 memory can rest assured that all the components in the board are made by IBM Corp, even if the boards were reconfigured by outsiders, but this assurance of True Blue components is more than IBM can give buyers of 9121 mainframes, reports this month’s issue of our sister publication Infoperspectives International: the chips used on 9121 memory boards, according to technicians who have closely examined them, are standard DRAMs made by Toshiba Corp, mounted on carriers called SIPs and they are believed to be rated at a cycle speed of 65nS; IBM sells this memory for $2,100 a megabyte but one of our favourite mail-order shops in California sells industry standard SIPs that work just as well as the Toshiba parts in IBM machines for $64.95 a Megabyte; however, say our friends in the components business, their SIPs are rated at 60nS, 10% faster than the ones in IBM mainframes; we guess that if you want real IBM parts in your machine, you may have to buy ersatz IBM memory, but if you want genuine Toshiba circuitry, you can always go to IBM – is all that perfectly clear now?
