When I ordered my brand-new super-quiet Intel box with 4GB of RAM, I knew that there were issues with the 4GB limit of 32-bit OSes. Little did I expect that a couple of hours Googling and reading would leave me completely befuddled. Before I spend more hours testing endlessly, I would appreciate input on the best compromise in the "real world". BTW, I am highly comfortable with Kubuntu Gutsy Gibbon; I will install it first. There is lots of space available to try other distros later. Some sources say that the CONFIG_HIGHMEM4G configuration works for installations up to and including 4 GB RAM. Others say that one must use a PAE kernel (CONFIG_HIGHMEM64G) for installations of 4GB and up. My reading suggests that he latter group appears to be correct: If the first 32Kb of memory is reserved for PCI assignments, 4GB does not fit into (4G minus 32K). dmesg recognizes all 4GB but recommends the PAE kernel: [ 0.000000] Warning only 4GB will be used. [ 0.000000] Use a PAE enabled kernel. [ 0.000000] 3200MB HIGHMEM available. [ 0.000000] 896MB LOWMEM available. cat /proc/meminfo tells a different story: MemTotal: 3369808 kB MemFree: 2816504 kB Buffers: 81396 kB Cached: 342620 kB SwapCached: 0 kB Active: 210868 kB Inactive: 285996 kB HighTotal: 2489856 kB HighFree: 2068024 kB LowTotal: 879952 kB LowFree: 748480 kB SwapTotal: 0 kB SwapFree: 0 kB P.S. Because this is a "just home from the store" system running off a LiveCD, the hard disks are not yet partitioned and there is no swap space. I will correct this during the OS install. Q. Some sources state that enabling PAE in the kernel leaves a significant performance hit. All these sources are two years old or more. Is this problem inherent or has it been worked around? How significant is the hit? Since the default Ubuntu kernel on the LiveCD acknowledges ~3.3 GB of RAM, should I consider "leaving alone"? Q. A posting by Falko Timme on howtoforge.com from mid-December 2007 states that there is a bug in the GRUB implementation on Debian Etch which prevents the system from recognizing more than ~3.3 GB RAM. (The exact figure on his 6GB system was a little higher than on my 4GB system.) He offers a patch and recommends recompiling GRUB. Does anyone know if the version of GRUB in Ku/Ubuntu 7.10 Gutsy Gibbon contains the same bug? Thanks in advance for advice on these questions. P.S. Since posting the above first on ubuntuforums.org, I have learned that the so-called "amd64" 64but versions work perfectly well on my Intel Core 2 Duo E2160 processor. My recall is that there now exist satisfactory solutions to longstanding problems with Flash, the nVidia proprietary blob, etc. Off to do more Googling. -- Bruce Miller Ottawa ON, Canada bruce [ at ] brmiller [ dot ] ca (613) 745-1151 This message is from a webmail login and not from my regular mail system. It does not have my customary digital signature.