How much maximum memory can I use with a DG43NB?

How much maximum memory can I use with a DG43NB?

I have a DG43NB motherboard which I'm using for almost 4 years to drive a
Q8400 with 4GB DDR2 800MHz RAM. That's because it's spec says that it
supports maximum of 4GB RAM. But here the G43's details says that for DDR2
the chipset supports up to 16GB. And this shows that at least a total of
8GB 1066MHz DDR2 can be used with the board. Now, I really need to
increase memory of this system. So, the question is how much maximum RAM
(and of what speed) can I use with this board?
Note: I have another much high-end machine, so please don't suggest to go
for a higher platform instead.