Precision 690 Memory Upgrade - why won't this work?

[maxamillions]

Can someone tell me why this won't work? It's Hynix:

1GB 2R8 PC2-4200F-444-10
HYMP512B72P8-C4 AB 0512

It's fully buffered, 533MHz, ECC. I get the error light 1 when I put it in by itself and lights 1 and 3 when I put it in with some known working, compatible ram. I've been over this a hundred times and I can't figure this out. It looks like this:

http://i17.ebayimg.com/04/i/08/7e/2e/35_1.JPG

 

[John]

It's quite possible that it's a defective stick of memory. Try it in another computer if possible.

 

[maxamillions]

I bought 6 and none work in any of the Precision 690s I have :-(

I just want to know why so I don't make the same mistake again. All the numbers and stat suggested it would work. The only thing that's off from the current ram I have in the machine is the number at the end of the first line:
1GB 2R8 PC2-4200F-444-10

what's on the working ram:
1GB 2R8 PC2-4200F-444-11

 

[TG2]

Your installing in pairs, correct ?
The stuff already in there is ECC as well ?

What happens taking a stick from another working 690 and putting into another:>

- same problem or works fine ?

 

[maxamillions]

Originally posted by: TG2
Your installing in pairs, correct ?
The stuff already in there is ECC as well ?

What happens taking a stick from another working 690 and putting into another:>

- same problem or works fine ?

Thanks for the reply. Yes, in pairs and it only takes ECC. It works fine with ram from another 690. I just can't figure out why these won't work because all the numbers match up!