Windows 2008 R2 x64 Datacenter not showing all memory as usable

try this workaround
go to run>msconfig > boot> advanced options > maximum memory > write 32768 > reboot.

see http://support.microsoft.com/kb/978610

also you can try :
1 Enter BIOS
2 Advanced
3 Chipset Settings
4 Enable Memory Reamp Feature
5 Exit and Save

Hi,
Thanks for tip I did that but still the same issue.

Any further ideas ?

Thanks

are the RAMs installed in the correct order in their slots ?

Yes they do. Under msinfo32, it show installed memory as 32GB.

Thanks

Samir

did you upgraded the bios firmware ?

No.
can you help me with the steps to upgrade the bios on dell server as I have never done that.

Thanks

What was the setting in the BIOS for memory reamp ?

you have to get the bios update from dell website
http://www.dell.com/support/drivers/us/en/04/ProductSelector/Select/FamilySelection?CategoryPath=all-products%2Fesuprt_ser_stor_net%2Fesuprt_poweredge&Family=PowerEdge&DisplayCrumbs=Product%2BType%40%2CServers%252c%2BStorage%2Band%2BNetworking%40%2CPowerEdge&rquery=na

choose your server model, choose bios and windows 2012 then download the and extract then execute it.
Some bios updates needs to be burn to floopy or bootable CD and boot the server from the CD to update the BIOS.

before that try this trick . turn off the server, there is a guide for the memory order to be installed  in the slot ( usually written on the cover) . swap the RAM in the slots .

Hi,
I updated the BIOS to latest firmware but no luck.
Actually the RAM's were installed by Technical Engineer and they also arranged the RAM's on the slot. I guess they have arranged properly.

Thanks

Samir

Did you order the RAM directly from DELL?

What type of RAM have been installed in all slots?

The PowerEdge R710 uses DDR3 memory, providing a high-performance, high-speed memory interface capable of low latency response and high throughput. The R710 supports Registered ECC DDR3 DIMMs (RDIMM) or Unbuffered ECC DDR3 DIMMs (UDIMM).
The system contains 18 memory sockets split into two sets of nine sockets, one set for each
processor. Each nine-socket set is organized into three channels of three memory sockets per channel.

Key features of the R710 memory system include the following :

Registered (RDIMM)
and Unbuffered (UDIMM) ECC DDR3 technology

Up to 288 GB of RDIMM memory (eighteen 16GB dual rank RDIMMs)

Up to 24 GB of UDIMM memory (twelve 2 GB UDIMMs)

Support for 1066/1333 MHz single- and dual-rank DIMMs

Support for 1066 MHz quad-rank DIMMs

Support for 1.35V low voltage
(LV) DIMMs with 5600 series processors

64 data and eight ECC bits per channel

Support for single DIMM configuration (DIMM in socket A1 only)

Support for ODT (On Die Termination) clock gating (CKE) to conserve power when DIMMs are not accessed (DIMMs enter a low power self-refresh mode)

I2C access to SPD EEPROM for access to RDIMM thermal sensors

Single Bit Error Correction

SDDC (Single Device Data Correction, x4 or x8 devices)

Support for Closed Loop

Thermal Management on RDIMMs and UDIMMs

Multi Bit Error Detection Support for Memory Optimized Mode

Support for Advanced ECC mode

Support for Memory Mirroring

Support for Memory Sparing with 5600 series processors

7.2 DIMMs Supported
The DDR3 memory interface consists of three channels with up to
three RDIMMs or two UDIMMs per channel for single or dual
rank and up to two RDIMMs per channel for quad rank.

The interface uses 2GB, 4 GB, 8 GB, or 16GB RDIMMs.

Also supported are 1 GB or 2GB UDIMMs.

Source: http://www.dell.com/downloads/global/products/pedge/en/server-poweredge-r710-tech-guidebook.pdf

http://community.spiceworks.com/topic/268488-ram-config-for-dell-poweredge-r710-single-cpu

Please can you tell me the name of the utility where I can generate memory details. As I can shutdown the server and get the specs.

Thanks