-----Original Message----- From: Ward Vandewege [mailto:[email protected]] Sent: Friday, November 05, 2010 01:42 PM To: Scott Duplichan Cc: 'Peter Stuge'; [email protected] Subject: Re: [coreboot] [PATCH]Move QRANK_DIMM_SUPPORT to Kconfig
]On Fri, Nov 05, 2010 at 01:28:59PM -0500, Scott Duplichan wrote: ]> I am no quad rank dimm expert, but I think few boards support them. One is Serengeti ]> Cheetah. I remember asking why one processor socket has 4 dimm slots and another 8. ]> I was told it was for quad rank dimm testing. The chip selects for two normal dimm sockets ]> are combined and routed to a quad rank socket, if I remember correctly. I don't even ]> have any quad ranked dimms to test with. I think they are rare. ] ]Actually, they are not *that* rare, since they are readily available: ] ] ]http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=ddr3]+quad+rank&x=0&y=0 Sure enough. And not a bad price (per MB), either. Thanks for pointing them out. Though I would question the maturity of coreboot support for registered DDR3 in general, and specifically for 1333 speed or quad rank. I believe these were perfected internally at AMD only recently. How well has coreboot been tested with various speeds of registered DDR3? There is a lot more complexity in the memory init code when registered DIMMs of any rank count are used. And there is still the question of what boards supported by coreboot really have hardware support for quadrank. I would hate to mislead someone into buying a system loaded with registered memory with the idea of running coreboot, unless it is known to work. Thanks, Scott ]-- ]Ward Vandewege <[email protected]> ]Free Software Foundation - Senior Systems Administrator -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
