We've reviewed two such devices right here on CNET. NET Compact Framework 1. Programs and frequently accessed data run in RAM, while most storage is in the flash memory. Everything is backed up in the flash memory, so unlike prior devices, WM5 devices lose no data if power is lost. This continued the trend of Windows-based devices moving from using RAM as their primary storage medium to the use of a combination of RAM and flash memory in use, no distinction between the two is obvious to users. And lastly, you'll have to find the firmwares online and some of them are homemade concoctions which don't always work, so be careful and do some reading before you go ahead with this. This is because a backup made when running an older ROM version can't be restored to a newer version, leaving you without a leg to stand on should the device fail.