According to Fudzilla, the GeForce 9800 GX2 could be equipped with 2 GB of memory.
In practice, this figure is actually reduced to 1 GB because each of the two GPUs has its own memory which implies that data has to be stocked twice as is also the case with two cards connected in SLI.
Contrary to some preconceived ideas that suggest each increase in memory is a purely marketing maneuver, we were able to see in our latest tests
that 512 MB is more and more insufficient in very high resolution and with antialiasing activated. For this reason, the 2x1GB will be far from being unwelcome on such a card.