Summary: Debian Squeeze 64-bit was not able to use more than 3.6GB RAM. Linux showed the problem as MTRR not covering all available RAM. MTRR problems can be fixed by kernel if MTRR repair is enabled, e.g. in the 3.2 kernel. However, the using the backported 3.2 kernel resulted in kernel panic.
As RAM had been tested extensively with memtest, the problem was hypothesized to be because of faulty motherboard or BIOS. One RMA of MB later, and everything is working with the 3.2 kernel and "noapic irqpoll acpi=force" boot flags. I did have a small problem: Sometimes I would get "RAM R/W test fail" at BIOS POST. I tested if the individual DIMMs could POST, only one gave the "RAM R/W test fail". After removing the 'faulty' DIMM + a healthy DIMM, the system works smoothly. I have not had time to test the 'faulty' DIMM in another computer yet to see if it really is faulty. Thank you all for your help! -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/1338522341.4810.23.camel@smh-tablet
