Comrade urbanstyles,
So as we are to understand it, there is no video, no post, nothing. The problem, then, is clearly more deep seated than simply a failure to recognize the new memory: You can't even get into set-up.
First, consult ASUS about resetting CMOS and, if you determine that there is nothing to prohibit what I'm about to suggest, using only the RDRAM that worked originally and after having reseated the video card, unplug the computer from the power source, remove the CMOS battery for a moment or so and replace it, reconnect the computer to the power source and try to reboot.
It is our suspicion that Trotsky has had a hand in this, comrade urbanstyles. He will be paid in full.
Yours in the joy of socialist labor,
LavrentiBeria