If you're going to give him advice, at least make sure it's accurate. Windows 8 has no such problem with memory. This is coming from someone who uses Windows 8 as the daily driver, with 16GB of fully functioning RAM. It's quite sad how many lies are spread about Windows 8 (though I'm sure you thought you were helping and telling the truth).
Windows 8 is not the issue here. Your RAM sticks are very likely the issue - they probably aren't seated properly. The only fix is to re-install them and ensure they're firmly secured inside the motherboard. If that is done, and they aren't working correctly, one or more of your RAM sticks is defective.