2G.i'msure...

The D70(s) can use FAT32 file systems on the memory cards, so in theory
they can use cards up to 8 terabytes. FAT32 specs allow up to 8
terabytes, but the firmware in the camera may limit the capacity to
32gigs (possible format limit) or less. Large cards were not available
when the D70 was first produced.

The D70(s) is known to be compatible with cards up to at least 4gigs. If
you want to use a larger card than that, take it in to a store and
confirm it works with a larger card.

i use a 4 GIG  Ultra II Sandisk  in  my  D 70S  ti  works  great
it  shows 734  in raw

JOE

If it worries you, try it out first. I would be surprised if any of today's
cards are too large.

However, 4G is pushing your luck in another way: cards go bad, usually at the
worst possible time. If you have 4G of pictures you just might prefer losing
only 1G instead of all four of them. Better to have four smaller cards than
one big one. Changing cards takes only a few seconds. I believe it was Scott
Kelby who suggested that keeping 75% of the pictures from that wedding shoot
instead of 0% might keep you from having a little heart-to-heart talk with
the attorney representing the parents of the bride, if you know what I mean.
I have used a 4G card in the D70, but the reason I have 4G cards is for use
in the D200 shooting NEF format. Use in the D70 is incidental. I prefer much
smaller cards with that camera.