Third card I had is the 8GB Patriot SDHC card that worked without problems with 3.... firmware and using the SDHC kernel patch. I had that about 5-6 weeks running. It was in the internal slot. Once I updated to the latest 4.... firmware the 8GB Patriot card corrupted after about a week use. It was in the internal slot. It happened when I was on road trip using Maemo Mapper. It seemed to happen when the N800 was in "sleep mode" (display was dark) and likely there was simultaneous download of map file from internet (using phone as a DUN modem). Maybe the file system and ethernet have some critcal processes that can cause the file system not to write properly to the card and corrupts it??? Reformatting the 8GB card recovered it, but I put it aside now until a real fix is found for this issue!