This process simply entails re-formatting your card through the PC. After putting your PSP in "USB Connection" mode and seeing the drive letter appear in windows we need to reformat. Your formatting tool should provide an option for Cluster Size (possibly called "allocation unit size"). Sony announced on June 1, 2009, that M2 support in Sony Ericsson phones would be dropped in favor of microSD. [31] You can manually recreate this structure by copying it from another working card that formats successfully in your PSP. You may see some information/verbiage that states the PSP or the adapters support only SDHC cards. This is only because SDXC cards were not around when these devices were made there was only SD and SDHC format. So, the SDHC verbiage was meant to say "hey, we support the larger size SDHC, not just SD!" The same is still true in that the SDXC will work fine and indeed must be used if you want to use MicroSD cards beyond 32 GB.

I have personally confirmed mixing and matching of MicroSD cards of different sizes and speeds (although they were all the same brand - SanDisk). For instance I installed a 64 GB with a 16 GB to get ~72 GB (after format) of usable storage. You should dissconnect from the USB connection and restart your PSP several times to ensure that the card continues to be detected. Additionally, the adapter you use may determine the maximum amount of memory (based on what it can support. If it doesn't show the correct space then you won't be able to continue on with the next stage of configuration.

NOTE: If you plan on using only a single MicroSD card in a Dual adapter, place it the slot labeled "1" (top slot). There are more cards than I have shown here but for the most part the taxonomy above will at least allow you to select and try different types of cards. Last identifying trait I want to point out on this front picture is the plastic used. Specifically, if you look at #1 (the genuine article) you can see that the plastic is of a translucent type. If you look at the area circled in green you can see the internal circuit board of the chip. This isn't just because the material is thin and flimsy like #3 it is actually one of the more quality cards in terms of construction. You don't really need to worry about this because the genuine PhotoFast is the only one I've seen that has this translucent appearance, but it is good to know in identifying an original. You may opt for a smaller card and use CSOs to save space. Comparable to the speed differential, many games can be compressed considerably from their ISO forms.

It is probably wise to stay with the name brands of memory (Sandisk, Transcend, PNY, etc.) And, since you won't necessarily see speed improvements with the newest and fastest cards you can probably buy the lower end of the more modern cards. Have some spare ones sitting around that are a few years old? They will probably work just fine. While it is possible to go 400 GB+ larger cards are going to have speed penalties when loading the card. If you had a "Format completed" message on your PSP and #1 above is true you can likely stop here and just start using the card. In practice however the PSP is likely to give you several different kinds of "Format failed" errors.Next is lettering. Here I mean both font and verbiage. The font is very similar on most cards, though some have a slightly stronger/bolder printing that might help you distinguish between them. But, more visible are simply the words. Many will state "PhotoFast CR-5400" as highlighted by the blue rectangle (which they aren't). The rest will just print a generically more honest "MS Pro Duo" and "Dual Slot Adapter." After many tests I decided that it was unlikely I was going to ever get a clean format on anything over 128 GB. After reading rsn8887's thread above and seeing that he encountered the same issues I did I gave in to the fact that I probably have to rely on Windows to properly format the cards.