Memory requirements on 3640 router

[mitchen]

Hi,

I am due to upgrade the memory on a Cisco 3640 router.

It currently has:

64Mb DRAM consisting of 4 x 16Mb (Banks 0 - 3)

16Mb flash consisting of 1 x 16Mb (Bank 0)

I intend to replace 2 of the 16Mb DRAMs with 2 x 64Mb DRAMs in Banks 0 and 1

And to upgrade the flash by adding another 16Mb to Bank 1 (currently empty)

This would give:

160Mb DRAM consisting of 2 x 64Mb in Banks 0 and 1 and 2 x 16Mb in Banks 2 and 3

32Mb Flash consisting of 2 x 16Mb in Banks 0 and 1

Is this valid?

The parts I have are MEM3660-2X64D (Note: it is a 3640 router I will be upgrading though) and MEM3600-16FS.

I've never added memory before so if anyone can offer advice, precautions to take, what to look out for etc then it would be welcome.

Thanks.

[Kevin Dorrell]

Frankly, I don't know. I did find you the document about the memory in the 3600 series, but it does not mention any combinations with 64 Mb parts in a 3640. But it does mention 64 Mb parts in a 3660, and a different type of memory at that. Sorry, I get a bad feeling about this. But please do let us know the outcome.

Here is the doc, FWIW:

http://www.cisco.com/univercd/cc/td/doc/product/access/acs_mod/cis3600/hw_inst/hw_notes/3636mem.htm#wp112612

Kevin Dorrell

Luxembourg

[mitchen]

Hi Kevin,

thanks for the reply. Yes, thats exactly the info that I had been looking at and thats what got me worried in the first place!

However, I've been assured by a colleague that this memory can fit in the 3640 as planned.

But I'm worried - don't want to be held responsible if it all goes wrong (it was my colleague that ordered the memory but its me that will be carrying out the upgrade!)

Anyone know for definite what the memory situation is for the 3640?

[dan.gregoire]

I would have to agree with Kevin for 3 reason's.

1. The memory you have is for a 3660 and not the 3640. The 3640 uses SIMMs and the 3660 uses DIMMs, which are no interchangeable.

2. The max amount of DRAM the 3640 will recognize is 128MB.

3. The max SIMM you can install in a 3640 is 32MB. The 3660 can see 64MB DIMMs since it's max capacity is 256MB.

I hope this helps.

[mitchen]

Hi dan.

yes, seems like it was as we feared. This was indeed the wrong memory that I was supplied with. Having opened up the router to confirm, your reasoning above would seem to be 100% correct

Oh well, just have to wait till I'm given the right memory before I can carry out this upgrade then!

Thanks.