Yep. Dell and HP really ate Sun's lunch in the huge server space. It seemed to happen so fast.
It happened in 1 iteration from Sun's very successful E10k Starfire Enterprise Server. The next server was literally Bigger, slower, hotter and much more expensive than it should have been.
The reason was simple. Sun acquired the Cray Research server division from SGI when the E10k was already in beta and set to be released in months. The E10k was not designed by sun. It was designed by Cray Research Engineers in San Diego. It was very successful and accounted for over 10B in revenue over 5 years. The next generation server E15k/25k was designed with "too much" help and "too many" architectural constraints from Sun's Legacy Engineer from the Bay area.
There was much swearing and gnashing of teeth at the San Diego development center. I think a few chairs were thrown too.
By the 2nd iteration we were buying ready made servers from Fujitsu and integrating disks and memory. It was sad and over. Then we were bought by Oracle, but I had retired by then.
The San Diego design team was great. Much better than the Sun legacy design team. Engineering graduates from Stanford are very over rated. Rensselaer engineers are very underrated. Oh well, thanks for letting me reminisce. If I had to do it all over again I would have stayed at Cray Research.