Why am I getting 923.18 Gh/s from Antminer S3 and S1?

[paramind22]

I just noticed at my pool I'm getting 923.18 Gh/s from my Antminer S3 and S1.  I got them used
and I don't know about any overclocking settings on them.  The Gh/s should be around 575 to 700. 
I'm using Eliguis for the pool. 

[paramind22]

I just rechecked the settings and its now at 273.54 Gh/s.  

and a few minutes later now 718.03 Gh/s.  I'm not worried just wonder what the pool mechanics are that do this and that it's not on my side but something happening at the pool.

[gt_addict]

This is perfectly normal. All mining machines do it. It's just a variation on how quickly the chips are processing the work. When you have a look on the GUI it will read the correct Ghs and also on the pool it will read the correct Ghs on each shift.

[unholycactus]

Your sample size to evaluate your hashing was simply not big enough.
You probably just started them and recorded a spike.

You're right to say that over a long period of time it should be around 600 or a bit less.