That looks correct. There are two timings available (I guess this is in the bios) and you are using the 400Mhz timing.
With DDR2 you need 2 matched DIMMs to get the double-data rate of 800Mhz. If you have 2 DIMMs you should make sure they are in the right slots. They should go in slots 1 and 2 which are NOT next to each other on the last dell MB that I saw.
The slot numbers on the last Dell I saw were: 1, 3 and 2, 4
You also have ECC ram which I assume is why your timing is 5-6-6-18.
With DDR2 you need 2 matched DIMMs to get the double-data rate of 800Mhz. If you have 2 DIMMs you should make sure they are in the right slots. They should go in slots 1 and 2 which are NOT next to each other on the last dell MB that I saw.
The slot numbers on the last Dell I saw were: 1, 3 and 2, 4
You also have ECC ram which I assume is why your timing is 5-6-6-18.