Originally Posted by alcimedes
That's fucking bullshit. However, they will ask you to remove 3rd party RAM before you send it back to them if it needs to be repaired so they can rule that out. They don't like testing other people's hardware.
Of course, you should always remove 3rd party RAM when troubleshooting hardware problems, anyway. And definitely remove it before sending the machine to Apple, whether they ask you to or not.