HP Blades with AMD CPU support up to 128 GB of RAM. We have 3 x AMD with 128 GB and 3 x Intel 64 GB. The new intel HP blades support 144 GB RAM. At peak each varnish server is handling 40k established connections, not active connections as I wrote by mistake. About 7000 to 8000 hits per second. Posted at Nginx Forum: http://forum.nginx.org/read.php?2,615,1011#msg-1011