Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!usc!apple!voder!nsc!amdahl!JUTS!cd!wps10 From: wps10@cd.amdahl.com (Wilson P Snyder) Newsgroups: sci.electronics Subject: Re: ECL logic computers ? Message-ID: Date: 27 Jun 91 20:41:51 GMT References: <7183@gara.une.oz.au> Sender: netnews@ccc.amdahl.com Organization: Amdahl Corp., Sunnyvale, CA. Lines: 21 In-reply-to: rbennet1@gara.une.oz.au's message of 26 Jun 91 14:21:46 GMT ECL in computers? Most of the big mainframes use ECL, (recent Cray models excepted) but it costs mega bucks. Amhahl's most recent announced processor, the Amdahl 5995, has a 7ns cycle time (~150 Mhz). The CPU dissapates several kW of heat in roughly a tenth of a cubic foot. Needless to say, this requires liquid cooling. Indeed a 8086 could be put into ECL, it would be much faster then the above, as it wouldn't have all of the complexities of a mainframe CPU. Unfortunately, I don't think most people want a car sized water chiller, $50 in power every hour (CPU + power + cooler...), especially for a pricetag in the hundreds of thousands. Realistically, there are other types of logic that are being developed that offer simular speeds with much less power. This is what will be under the hood of the 1000 Mhz CPU that a group at my school (Rensselaer Polytechnic Institute) plans to have working in 2 years. (DARPA Funded.) Unfortunately, these new logic families don't yet enjoy mass production, so the cost is still up there. P. S. I could build a 10 THz+ computer with ECL now - but I'll leave you in charge of the cooling system.