So, the latest news is the RAM is not bad, so that's not it.
Hosting company claims to have removed the KVM add-in board, but they refuse to actually go to http://www.sott.net to see that no, in fact it is still there!
I can't seem to get a straight answer from them as to why this screen is there, if they changed the network/server in some way (they did, on August 12th, when they upgraded their datacenter), and so on...
In short, I think they changed something and broke it, but they won't even acknowledge that all of us are seeing the Asus iKVM login screen.
It's a bit like pulling teeth at this point...