My first instinct is that Knoppix is a 32-bit kernel and so is unable to address all of your memory except 4GB minus whatever the video card wants. However, I'm no memory expert, so I could be wrong.
I am running Knoppix 5.1.1 on an AMD Athlon II X2 235e processor system with 6GB RAM, and would like to use all available RAM. For some reason, Knoppix only uses 3GB RAM, no matter what value I assign in the "mem=" command line cheat code.
Any ideas?
knetter136
My first instinct is that Knoppix is a 32-bit kernel and so is unable to address all of your memory except 4GB minus whatever the video card wants. However, I'm no memory expert, so I could be wrong.
Hmm-Originally Posted by garaden
I've read that Windows 32-bit kernels can't go beyond 3GB too; but that is no reason a Linux kernel can't do it. Maybe some lucky guru will spot this here and enlighten us all...
-Krishna
Ok, did a little more research and found out that a mechanism called Physical Address Extension is required to access extra memory using 32-bit OSs. Unfortunately, activating this mechanism results in kernel modules that won't work on processors that don't support it. Most (all?) modern processors support it, but Knoppix doesn't seem to be built that way for compatibility with old machines. Go here if you want a package that supports this capability (you can enable/disable PAE at will using various Grub entries included in the package). Unfortunately it's a few months out of date, but oh well.
Good luck!
Dell PowerEdge R720 Server - 2x8c CPU,256Gb RAM, 128Gb SSD/3x900Gb SAS, Proxmox
$340.00
Dell PowerEdge R620 Server 2x E5-2660 v1 2.2GHz 16 Cores 256GB RAM 2x 300GB HDD
$89.99
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
CTO Dell PowerEdge R630 Server, 2x Xeon E5-2620V4, 64GB- 512GB RAM, 480GB SSDs
$246.67
DELL POWEREDGE T430 SERVER W/ DUAL XEON E5-2609 CPU & 16GB MEMORY
$329.00
Dell Poweredge R620 8-Bay CTO Pick your CPU & RAM Config | H710 Raid | 2x PSU
$209.99
Dell Poweredge T430 8 Bay Server Dual Xeon E5-2683 V4 32 Cores 64GB DDR4 2X SSD
$799.00
Dell PowerEdge R620 4-Bay Server 2x Xeon E5-2690 8 Core 2.9GHz 32GB No HDD H710P
$95.63
DELL PowerEdge R730 Server 2x E5-2680v4 2.4GHz =28 Cores 32GB H730 4xRJ45
$284.00
PowerEdge R710 Rackmount Server 80GB RAM 2x XEON E5520 CPU 4.75TB
$200.00