NovaTac 120P + near depleted cells = no light?

I have a few really depleted cells lying around that I decided to test in my new 120P (I figured I'd be able to get some use out of them... at least on the lowest setting).

I had 2 cells from my A2 that stopped lighting up the incan a while ago... still had a few hours more running the LED's so they were pretty empty. I tried them in my 120P, and nothing. I tried them individually in my SF L1 cree and it still lit up in low mode, but direct drive significantly lower than the regulated low. Nonetheless, it still lit the L1 cree but nothing in the 120P which was a little disappointing.

So right now I have 2 cells that will work in the A2 LED's that has a rated runtime of 20 hours, works in my L1 cree with a listed runtime of 16 hours, but doesn't work on any brightness level in my 120P which is supposed to last hundreds of hours on the lowest setting... =(

Is there something special I have to do after I put in a new battery to get it to light up? I know I have to do a battery reset for switching from RCR's to primaries but I'm only switching from the original Duracell primary to a depleted Surefire primary.

the novatac does not drain batteries as well as the hds did. from what i have herd. There is nothing special you have to do to put in a old cell .