Either a bad connection in the dash or a bad connection under the hood. No idea where the RPM sender is (maybe it comes right from the computer, dunno). But the boost gauge sender is above the passenger side fender. You should see a vacuum line going into it, which connects to the back of the intake manifold right behind the turbo (you probably won't be able to find that end of it). Pull the sender end of the vacuum hose off, make sure you've got vacuum there when the car runs, if so, then the sender connection's ok, but the senser might be screwed. But since both ur RPM and boost don't light up I'd guess it's a dash thing.
Good luck... Let us know if you find anything!
Dave