Why didn't my new RAM work (T400)?

[Oro]

I purchased a 4GB Samsung DIMM to upgrade the memory in my T400.

I did some research and saw that they could sometimes be finicky so I ordered a PC3 2-Row, Samsung 12800.

I received a PC3L and it was 1 row. Is that likely the reason? Likely the 1 row issue, or also the low-voltage? What do I need them to send me to make sure it will be compatible?

Thanks!

[CASPER]

Yes, the 1 row is the issue, I've read about people having problems with 1Rx8 DIMM's in T500's, T400's, etc. I think that low voltage module will work fine as they are capable of running both standard voltage (which T400 requires) or low voltage. I think I put low voltage modules in my T500 and it works without single problem. What you need is 2Rx8 module.