On Sat, 2006-07-15 at 15:42 +1200, Hadders wrote: > Tom Horsley wrote: > > On Fri, 2006-07-14 at 21:52 -0400, Tom Horsley wrote: > > > > > Is there some known problem with > 2 gig of memory and > > > the onboard usb with the x86_64 kernels? > > > > > > > Sure enough, when I take out the extra gig of memory, > > the scanner starts working and the boot time USB errors > > go away. I guess I have a spare gig now (which is all > > it really was before - I just thought I'd put it to > > use :-). > > > > > It's often been an historical fact that PC chipsets (not server class) > often don't like addressing large amounts of memory and require > particular DIMM configurations. > They also get fussy about EXACT memory timings. Check your mainboard > manual (asus are good for providing this as a download) for > recommendations on what banks can be used to get to 3GB. Oh, I did all that. The memory has identical timing and the i386 kernel as well as memtest86 has no problems, it is only the x86_64 kernel that has USB troubles. I suspect some sort of IOMMU nonsense, but the simplest fix is to just leave only 2 gig in the machine in any case.
