its 64 bit - (first post) actually this is a dell 9100 (desktop) I had 2 pairs - 2gb each of ram different manufacturer actually I have 3 pairs of 2gb - any combination has the same results in memtest 1 pair in white 1 pair in black boots without memory beep errors memtest fails badly on any test with 8gb bios sees the memory I was running 2 2 gb originally now I have 4 1gb - so each slot is used and it tests perfect Basically this is a lab setup for a 4 node hadoop cluster. This is the head node and needs the most ram - Id really like to get 8 but Ill live with 4 (if I have to) So should my kernel support > 4gb? see below Thank you all for your time! ~~~~~~~~~~~~~~~~~~~~~~~~~ details dime910 /home/robert # uname -a Linux dime910.hadoop.lab 2.6.32-431.23.3.el6.centos.plus.x86_64 #1 SMP Wed Jul 30 00:12:13 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ dime910 /home/robert :( # dmidecode -t 17 # dmidecode 2.12 SMBIOS 2.3 present. Handle 0x1100, DMI type 17, 27 bytes Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: DIMM_1 Bank Locator: Not Specified Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: 7F7F7F7F7F510000 Serial Number: 0820A113 Asset Tag: Not Specified Part Number: 64T128020HU3SB Handle 0x1101, DMI type 17, 27 bytes Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: DIMM_3 Bank Locator: Not Specified Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: 7F7F7F7F7F510000 Serial Number: 061D4B16 Asset Tag: Not Specified Part Number: 64T128020HU3SB Handle 0x1102, DMI type 17, 27 bytes Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: DIMM_2 Bank Locator: Not Specified Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: 7F7F7F7F7F510000 Serial Number: 061D4B12 Asset Tag: Not Specified Part Number: 64T128020HU3SB Handle 0x1103, DMI type 17, 27 bytes Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: DIMM_4 Bank Locator: Not Specified Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: 7F7F7F7F7F510000 Serial Number: 081FAF13 Asset Tag: Not Specified Part Number: 64T128020HU3SB On Mon, Sep 8, 2014 at 4:33 PM, Louis Lagendijk <louis at fazant.net> wrote: > On Mon, 2014-09-08 at 13:52 -0400, Bob Metelsky wrote: > > Hi I have a dell 770 > > bios sees 8g > Is this a PowerVault 770? > Accoding to http://www.dell.com/downloads/emea/products/pvaul/77XN.pdf > It does support only 3GB of Ram. Can you please post a complete output > of dmidecode. It may very well be a case where the on-board chipset is > limited to 4GB address space minus the PCI addres space that leaves only > 3 - 3.5GB ofg Ram space > > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >