PXIe-4080 AC Sampling

[SGDSGD]

Looking to determine the methodology on how the DMM acquires an AC signal. The specs don't call out the accuracy of the measurement nor its methodology on how the data is collected. The spec also references the PXIe_CLK100 as another source which doesn't clearly identify (to me) how its done.  Trying to measure freqs. of 1700-3300 with an accuracy of +/- 5hz.

Looking to find how the accuracy of the frequency/period measurement. Can anyone elaborate?

Thanks in Advance.