Well, I didn't. I wanted to "test" my Precision T7500.
The processing load is well distributed, and it takes about 50% of the processing capabilities. I'm testing ACR 7.4 for a file opened from Bridge.
You can take a look at the indication of the Back-UPS' monitoring software. I reckon this machine of mine is pretty hungry, eh? I love it.
Everything: Bridge, Camera Raw, Photoshop, and Lightroom 5 beta work very smoothly and the response of the actions is instantly visible. No loading bar that says: preparing/processing/whatever image.