Can anyone enlighten me as to how large amounts of RAM aid in the encoding process? Encoding video is hardcore mathematics, CPU-shredding stuff. Open up the performance tab in Task Manager on Windows and watch it during an encoding run (or use top on proper operating systems)... Last time I did any serious video work was with Premiere, Avid and After Effects on Windows 2000 with a single core 1.4 Athlon. Surely we must be knocking on for way over real-time 720p MPEG2 software encoding on high end systems by now?
When buying/building a system, just get as many cores per socket at as high a clock speed as possible as you can reasonably afford. Ignore the RAM; it's cheap as chips and can be bought as/when if you need. A dual-socket system with a pair of 6 core i7 chips, 16GB of RAM, SSD for OS and big RAIDed conventional HDs for general storage will romp home for many years to come no matter what you throw at it. It would also probably cost less than the piece of junk you bought from PC world 10 years ago which you threw in a skip in 2006.
That Nortel switch would have been a BayStack?
Was 5510s with MLT'd fibre uplinks to 10gig backplane passports back in the day. Budget not that fat any more.