Use 2x MEM-3900-2GB on Cisco 3925

[johnlloyd_13]

hi all,

we usually order and use 2x MEM-3900-1GB but our vendor sent 2x MEM-3900-2GB instead for our 3925 router/

we would like to use the 2x GB DRAM sticks and was wondering if it's possible?

per link below, it said 4 GB will be available in future and i'm not sure what it means (if future IOS release will support it?).

http://www.cisco.com/c/en/us/products/routers/3900-series-integrated-services-routers-isr/series-comparison.html

* Up to 2 GB available for use; upgrade to 4 GB will be available in future.

[Vinit Jain · Accepted solution]

Hello,

Cisco 3900 series router is capable of upto 4 GB DRAM but Cisco IOS is capable of only 2 GB DRAM. You can still use both the sticks, but if the IOS that you are running supports only 2 GB, then the you can see only 2 GB in the show version output.

Yes the future IOS will have support for 4 GB RAM. 

Also, there are some additional modules like WAAS Express module, which requires 4 GB DRAM. So, if you install 4 GB DRAM, it will work but the router might still show as 2 GB DRAM becuase of what IOS can support. Note that 4 GB can be installed and will work because the 3900 Series uses symmetrical DIMM modules for increased performance, meaning that two identical DIMM modules must be installed into both DIMM slots.

Hope this answers your question.

Regards

Vinit

PS: Please mark the question as answered if your query has been answered. Also, please rate useful posts.

[johnlloyd_13]

thank vinit!

is there any news or internal info from cisco that IOS 15 will support the 4 GB DRAM?

[Vinit Jain]

I will check and see if I can get any information.