The CPU/11 reading in CPUZ means that you are running no divider on your memory 1:1.
An easy way to think of it is this, the (11) is your cpu multi in your bios...so no matter what multi you are using 11, 10, 9.....your cpuz should match that if you aren't running a divider.
If you are running 300x9, and no divider, your CPUZ should show CPU/9
Or if you really want to get technical, CPU/11 means this.....CPU=cpu speed....divided by 11 = memory speed.
so if you are running 273 x 11 = 3,000mhz, divide by 11 = 273mhz on your memory.