Re: HELP! What kind of SD Memory Card does my Nokia N810 Need And What BRAND should I Buy
 

Endsormeans has topic about his n800 set up with 2 128gb cards, there is post form his signature:

Anyway, this is still related to the n800, but when the n800 is able to handle xtra capacity cards then n810 should for sure.

Re: HELP! What kind of SD Memory Card does my Nokia N810 Need And What BRAND should I Buy
 

ok....now..

yup 128gb cards can work.
I don't suggest it for daily.
I suggest a max of 32gb
sdhc (no fancy type...just a tried and true works..)
class 4

any higher a class rating makes for issues on the nxx0.
as has been mentioned in other threads...
look up estels old posts on the issues... if wished.

Re: HELP! What kind of SD Memory Card does my Nokia N810 Need And What BRAND should I Buy
 

Yep, Scrolling through the maemo forums I've found many posts about problems with higher than class 6 cards, escpecially when they were partitioned and handling os's and swaps.

My N800 was set up with sandisk's 32 and 16 gb class 10 cards, where both were partitioned and internal one handling os, swap and os related stuff and external one swap and media. I've never expirienced problems, at least not critical ones.

The baddest (haha, not sure if this kind of word exist) problem faced was problems with card detection after card swap without doing a reboot.

Second problem was about some performance bugs. I was never sure about my device using full potential of provided cards, but for sure it was better than using class 4 cards.