Just an observation - some of my programs seem to max out at 50% CPU usage (DivX Converter is one of them) whereas other seem to be able to use both processors at once (C2D E6600)...
|>> Re: So why some programs max out at 50% CPU Usage
Misleading article. I use a Mac running UNIX (OS X). My laptop is dual core and my desktop is 8-core. OS X balances single threaded apps amongst my cores very well. But, more importantly, the 'big' apps I use take advantage of the 2- and 8-cores: NewTek Lightwave 3D 9, Apple Final Cut Pro, Apple DVD Studio, Apple Motion, Apple Aperature, Adobe Photoshp CS3 Extended. Of course, there is processor over head, so 8 cores is not 4 times 2 cores nor 8 times 1 core. But the CPU monitor duirng a LightWave render shows all 8 cores maxed out. With 8-cores I can run encoding to DV formats in the background while rendering video effectsi n my editor.
So if you think software and operating systems don't handle multi-core software well, then all I can tell you is to ditch buggy, insecure Windows and run a 'real' industrial strength operating system and applications.