HP DL380 G5 memory configuration - best practise

[bordomavi1967]

I am planning to upgrade my servers ram to at least 16GB but i am not sure if purchasing 4 x 4GB or 2 x 8GB is better. Also in my recent configuration all ram slots are full and i wonder if i use these rams for the other empty slots reduces performance because of different sizes and breaking Dual modes.

You can find my recent configuration below. If i remove 512mb rams and insert 8 GB does it work and what is the performance. As far as i know it is recommended to place same sized rams in proper slots.

Total memory - 8192 Mbytes
Board 0
DIMM 1A ( DDR2-FBD - FBD ) 512 Mbytes (667 MHz)
DIMM 2C ( DDR2-FBD - FBD ) 512 Mbytes (667 MHz)
DIMM 3A ( DDR2-FBD - FBD ) 512 Mbytes (667 MHz)
DIMM 4C ( DDR2-FBD - FBD ) 512 Mbytes (667 MHz)
DIMM 5B ( DDR2-FBD - FBD ) 1024 Mbytes (667 MHz)
DIMM 6D ( DDR2-FBD - FBD ) 2048 Mbytes (667 MHz)
DIMM 7B ( DDR2-FBD - FBD ) 1024 Mbytes (667 MHz)
DIMM 8D ( DDR2-FBD - FBD ) 2048 Mbytes (667 MHz)
ECC memory installed Yes
Dual Channel Memory Mode Enabled Not Supported

[Prokopets · Accepted solution]

Hi!
Well... It's always trade-off between economics and technology. If you want to get the best memory performance, you should use symmetrical DIMMs, but if you're thinking about upgrade - you should use less quantity of big DIMMs. For example: you can remove all DIMMs exept 2Gb, fill the slots with 2Gb DIMMs, and get your 16Gb or RAM without any way to upgrade exept of trowing out DIMMs. The alternative way is to use 8Gb kits (2x4Gb). As for me it's the most optimal until 16Gb (2x8Gb) won't became cheaper then they are now-days.

Regards,
Philipp.

[bordomavi1967]

So if i remove 4 x 512 Mb rams and insert 2 x 8 GB, it will work but performance will be reduced because of different sized rams. Is it correct?

[Prokopets]

Well, even if it will be reduced, i really doubt that you'll notice this on real applications.

Regards,
Philipp.

[bordomavi1967]

So if i say that we are running Exchange 2007 on it. And while we have 8GB ram, server uses 12.4 GB. What would be your advise? Removing all rams and inserting only 2 x 8 or 4 x 4 or inserting them with 2GB rams?