Exactly as freethought said.
As we do full memory tests on anything we deploy (due to datacentre being 150 miles from our base), I did a full memory test on our RB1100 with the Kingston 2GB DIMM (same part number as freethought already quoted) installed and it passed no problems.
It was only when I attempted to format the microSD card that I had installed did I hear the familiar 'beep beep' from the RB1100 which indicated a reboot of RouterOS.
Two more attempts yielded the exact same results.
Tried the same thing on the second RB1100 we had bought as a spare - which hadn't yet had its' memory upgraded - formatted just fine.
So, on a whim, I upgraded it with the second Kingston 2GB DIMM I had bought for this purpose and it suffered from the exact same problem - the router simply rebooted when attempting to format the microSD card.
Replacing the memory with the stock MikroTik DIMM allowed the format to complete without any errors or rebooting.
Hope that clears things up!
Spilsby Internet Solutions
OK liteforce and freethought... as promised,
Today I looked around the office and couldn't find my 2GB Sandisk microSD card. But I did find my 16GB Sandisk microSD card so I hope you accept that as a good test subject.
I originally bought this card to test in the RB450G. While the 2GB card formatted quickly and easily in the RB450G, I could barely get the RB450G to format the 16GB card and I was trying to determine the RB450G maximum flash capacity. When I started formatting, I was immediately kicked out of Winbox. I could type things into the terminal and might see a character on the display in the next minute or two. It acted like it was crashed but instead, nearly all of its resources were devoted to formatting the flash card. Finally after about 30 minutes, the card was done.
So today, I took an RB1100 with 2GB RAM card installed and formatted the 16GB flash card. It had ROS 4.10 and RouterBOOT 2.27 installed. I saw similar results as with the RB450G but it completed the format in much shorter time. I suspect about 10 or 15 minutes but didn't have the available time to time it.
Then I changed to a different brand 2GB RAM card and repeated.
I verified that the RB1100 with either the Winpro RAM or the Crucial Rendition RAM from my earlier tests, formatted the 16GB flash card just fine without crashing.
Don't format a flash card while routing traffic though.. as I said earlier, I think there are way too many resources devoted to this formatting and nothing left for more general tasks.
I did prove that I could format a large flash card without crashing a 1.5GB RB1100. Now I think that we have thoroughly tested the two types of RAM that we are using for memory upgrades.