new Asus monitor can't get "red enough" for 5000k?

I got a new Asus PB238Q and the first thing I did was calibrate it using DisplayCAL and the puck from my Spyder3 Express. It went fine.

I've always calibrated my ViewSonic monitor at 5000k and I realized that I had calibrated the Asus at 6500K. So I tried to redo it at 5000 but that didn't go well. Specifically, when setting up DisplayCAL to get the RGB values equal before calibrating, the "red" slider on the monitor was all the way up to 100 but DisplayCAL still showed the red value to be way too low. I tried the calibration anyway and the resulting screen was way too cool.

Just for grins, I tried to calibrate the Viewsonic at 6500 and found that it has "too little" Blue to get all the DisplayCAL RGB sliders to match.

So the Asus seems to be deficient in Red, and the Viewsonic seems to be deficient in Blue. Is it common for monitors to be deficient in one color, or is this a problem with the monitor? Or DisplayCAL? or the puck? Or me?

Just in case anybody's watching this for info, the problem is solved. I moved the monitor from a VGA connection to Displayport, which changed the screen color drastically. I was able to calibrate at 5000K, and with the Viewsonic calibrated also at 5000K, they match really, really well.

FYI, I bought 5 Asus monitors (for 3 different systems) and could never get any two of them calibrated the same on the same computer. This was using DVI connections.