Quick check- PHP pages asking to be saved == PHP down

[SiD the Turtle]

I've been developing some scripts on my machine that work fine and so uploaded it to my webhost. I haven't had any PHP up there for a while and they've been a bit crap of late so who knows. But now when I enter the address of the page, it brings up a save dialog rather that parsing the page and outputting it. I've checked with the simplest hello world script, same thing.

Before I go and moan at the webhost, would I be right in assuming PHP is down on the webserver?