Talk:XDR DRAM

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This is really fast RAM. Why has it been so overlooked by every company but sony? 70.112.86.215 03:56, 4 November 2007 (UTC)

Information on actual module capacities seems rather sparse (I found none with my own admittedly half-assed search) so I can only assume they might actually be too fast- what good is having a 4GB/s transfer rate if the module only holds 1 or 2 GB anyway? Seems these are probably just too much money for too little- if any- benefit. --67.160.118.193 (talk) 02:02, 13 January 2008 (UTC)

It's probably because the memory isn't really any faster, but rather the speed of the bus is increased. Based on Rambus' documents, the memory chips themselves will run at 200MHz, the same speed as the fastest DDR, DDR2, DDR3, and RDRAM chips. Like those other technologies, XDR relies on core prefetch to make up this difference between bus speed and memory speed. Since XDR's memory bus runs at 3.2GT/s while the memory chips run at 200MHz, it's a good guess that the core prefetch is 16n deep. That is twotimes as deep as the prefetch on DDR3, and four times that of DDR2. That means the higher speed comes at the cost of higher latency. Induality (talk) 07:07, 18 February 2008 (UTC)