Is this RAM compatible with my Motherboard?

Im so confused! My current RAM has a sticker on it saying SDRAM in the top right corner but in the bottom left it says 256mb DDR,333.
Im worried the Module i purchased aint gonna fit in the slot OR/AND there will be a hardware conflict between my 256 module and the 512 module because on the site that shows info on my motherboard, it says:
Warning (Not all memory configuration qualified)

 

DDR is also known as DDR-SDRAM. How many notches/holes are there in your current stick of RAM?

 

There's 1 notch. If you mean notch as the gap that divides the 2 rows of pins.
This is where my worry begins because the RAM that i bought appears to have more pins on the right set than on my module.

 

Its fine. Modules will only go one way, the reason its like that is because its been flipped.
Since the gap is only on one side, how many pins there are depends on your perspective.
http://images-eu.amazon.com/images/P/B00006JDJI.03.LZZZZZZZ.jpg
http://i10.ebayimg.com/01/i/02/df/4b/9c_1_b.JPG
These 2 sticks are both DDR, but one pic is taken from one side while the other is taken frm another. If they were both on the same side they'd be identical.