I recently discovered that my RAM is faulty (MemTest86+). I am waiting for new RAM to be sent to me.  It was through sheer luck that I discovered something was wrong. I was copying a large amount of big files and decided to verify the copies by their checksums. I discovered strange discrepancies, and noticed that checksum computation for the same file was not consistent. Now, this is the only problem I have encountered; no BSOD, no crashes, no errors. In a sense this makes me more worried than if I would have had massive crashes. I have no idea for how long the RAM has been faulty, and I have no idea if corrupt bits have been saved into files on my hard drives. I do know the RAM was fine two months ago (tested it back then). I am a user of Adobe's Lightroom and I am worried that photos or the catalog itself could carry corrupt data.

Question: what should I do once new healthy RAM has been installed? Reinstall Windows (I'm using Windows 7, 64 bit)? Is there a risk that I will be presented with nasty surprises in the future if I don't? What about personal files? I have backups of some of the files but for newer files I'm not sure I can even trust the backups. It's going to take me many hard hours to manually replace files with older versions, or compare checksums.