this is the old machine i used years ago with mIRC, it's fast enough. (and yes, i'm using new box of cos)
but chance i run new mIRC on the old box, i noticed the display performance is really bad
1. when each new line comes out, the whole content of a window is redraw from top to bottom much slower than before
2. fast display isn't really fast indeed than case 1. it only update screen on every 2 newline regardless of how many/fast lines come out except for only 1 newline. why not just have a timer to do a delay?
3. alt+1,2 switch between windows, each switch make the window redraw 3+ times. this take much cpu even in my new machine on 1280x1024 screen