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Questions tagged [cray]

For questions relating to the supercomputers made by Cray Research and its successors.

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Why did the Cray-1 have 8 parity bits per word?

According to https://en.wikipedia.org/wiki/Cray-1 The Cray-1 was built as a 64-bit system, a departure from the 7600/6600, which were 60-bit machines (a change was also planned for the 8600). ...
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Did Cray computers use virtual memory?

I found a mention on page 777 of the Second Edition of the book "Computer Systems: a programmer's perspective" [Bryant - O'Hallaron] stating that Cray supercomputers still do not use virtual memory (...
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Why does the Cray 2 use 400 Hz power, and why generate that from motors?

This Cray sales brochure details on page 4 that the Cray-2 uses 400 Hz power, and generates this from motors. 400 Hz power from motor generators I'm not sure that in 1986, the state of the art ...