I'm specing out a new box to act as a tandem switch. It will have a TE410P with 4 x PRI and support IAX connections to four other boxes using predominantly ilbc and/or gsm. It also has 3 IAX trunks to Teliax for call routing also using gsm. No extensions actually terminate on the tandem, they're all switched to other boxes (highly distributed). On the PRI card, one goes to Embarq, the PSTN and two go to a legacy SX-200 which is being phased out. The fourth is a connection to an Adtran TSU-600 channel bank. Given this is a greenfield spec and we're building it from scratch, I'm looking at SuperMicro and their motherboards. Architecturally, I see the tandem as being CPU bound, if anything. Backbone is GigE connected to the server so I/O there isn't an issue and we aren't doing voicemail on it so it isn't diskbound. Primarily the load will in in transcoding between the PRI channels and the IAX channels. We're looking at probably no more than 100 calls simultaneously. All the remote boxes use the same codec on the channels, so it doesn't have to transcode for inter box comm's. How well does asterisk spread itself out over multiple CPU's (aka Cores). I'm looking at their 2xQuadCore (clovertown) motherboards and was spec'ing CPU's. I know this is a religious issue in some circles, but is it better to have one Quad core as fast as you can buy (4 CPU's) or 2 x Quad core at a lower speed (8 CPU's). Obviously, I've got to shoehorn a budget here and can do 8 for the price of 4 if * will spread itself out. If transcoding is threaded and doesn't deadlock for a single resource, it seems 8 cores would be better than 4. Thoughts? Thanks for any input. Eric