HP xw6600 RAM replacement - 4GB FB-DIMM 398708-061U

[AnfieldRoad]

Hi have an xw6600 Workstation which had 32GB RAM and has a faulty 4GB FB-DIMM memory module that needs replacing.   All modules in the system are HP part 398708-061U (Micron MT36HTF51272FY-667E1D4) with the blue heatspreader.

Given the age of this system I'm finding it very hard to find the module and have been looking on ebay.  I am finding there are lots of 398708-061 (ie minus the U at the end) but no 398708-061U.

Can anyone advise what the difference is between the U and non U module?

Any suggestions on how I can find some of these modules?   

Or if there is an equivalent module I can get that is easier to find?

I'm in Melbourne, Australia

Thanks

[DGroves]

i used to work on these systems many many years ago...................

i strongly recommend you dl the bios and other files (like the service manual) from HP as they will be removed by HP in the not so distant future

your modules are 2R (Rank) x4 PC2-5300 ECC (DDR2-667)

398708-061U is a just a HP internal part number and has nothing to do with the actual memory specs it's just a number that hp assigned to this module

you can ignore the "U" suffix it's not important, however if you insist on exact match they can still be found used on ebay from time to time

Update:

here's a link to the 6600 HP memory page

https://support.hp.com/us-en/document/c01319077

https://www.ebay.com/itm/172970156203

https://support.hp.com/us-en/drivers/selfservice/hp-xw6600-workstation/3432821