Question HP z420 workstation memory help?

[LoLLess]

Hi i have a HP z420 workstation with an e5-1620 processor and 8 dimm slots i just bought 2x16gb sticks of ram and need 2 know what dimm slots 2 put them in they are by themselves plz help

 

[clarkjd]

Welcome to Tom's!
Have you googled you PC? Should be able to find the manual on the HP website at least.

 

[william p]

If you go to HP and view the online owners manual you can get that info. But that's actually a 4 channel RAM system. You should get 2 more matching sticks. 4x4GB would be a correct 16GB setup.

 

[LoLLess]

so will the computer run with 2x16gb sticks?

 

[LoLLess]

Welcome to Tom's!
Have you googled you PC? Should be able to find the manual on the HP website at least.

i have. it only has 8gb sticks, 4gb sticks and 2gb sticks not 16gb

 

[LoLLess]

If you go to HP and view the online owners manual you can get that info. But that's actually a 4 channel RAM system. You should get 2 more matching sticks. 4x4GB would be a correct 16GB setup.

when i got the computer it had 1x2gb stick in dimm slot 8 and it worked and supposedly the 2gb should have been in dimm slot 1 not 8 so im confused

 

[clarkjd]

i have. it only has 8gb sticks, 4gb sticks and 2gb sticks not 16gb

Then I would think that the MBis limited to supporting only 8GB sticks. 16GB sticks may work, but it is an unsupported configuration.

 

[william p]

You will be losing performance if you make it run anything other than a 4 channel setup. Running a 6 core CPU with 12 thread cabability on 2GB may run, but you can't say it actually "WORKS". If you look at the configurations HP offered which should be shown in their manual then you will have something that will perform properly. The memory controller may or may not split those 2 modules into 4 channels for you. It may depend on which 2 slots they're in. This will depend on how the slots were configured by HP.
http://h20195.www2.hp.com/v2/getpdf.aspx/4aa3-9557enw.pdf

 

[LoLLess]

You will be losing performance if you make it run anything other than a 4 channel setup. Running a 6 core CPU with 12 thread cabability on 2GB may run, but you can't say it actually "WORKS". If you look at the configurations HP offered which should be shown in their manual then you will have something that will perform properly. The memory controller may or may not split those 2 modules into 4 channels for you. It may depend on which 2 slots they're in. This will depend on how the slots were configured by HP.
http://h20195.www2.hp.com/v2/getpdf.aspx/4aa3-9557enw.pdf

ok ty i hope it works... atleast it will be better then 2 gb ram

 

[LoLLess]

so even though the mb says i have the 2 gb stick in slot 8 and online it says 1 stick should be in slot 1 the motherboard is probably printed wrong?

 

[clarkjd]

so even though the mb says i have the 2 gb stick in slot 8 and and online it says 1 stick should be in slot 1 the motherboard is probably printed wrong?

Theoretically, a single stick should "work" in any slot. It will just be more stable if you put it in the recommended slot.

 

[LoLLess]

Theoretically, a single stick should "work" in any slot. It will just be more stable if you put it in the recommended slot.

oh ok ty i bought it from an army surplus and it just came that way been trying 2 figure out how it was even "working"

 

[william p]

They probably just stuck a module in to show that it can boot. It's not uncommon for a "barebones" system to come without everything actually required to function properly. It's also not uncommon for computers to suppport larger modules than were offered originally. They double in size very couple years.
Memory needs to rest every few cycles to refresh. Multiple memory channels allow the RAM to keep working while other modules are "refreshing". Faster multicore CPUs need more channels to support their speed, and bandwidth.
Dual channel memory was last used in a workstaion on 4core 4 thread systems in the LGA775 era.
I'm not saying it doesn't work. Runs just fine in my $20 Optiplex 380.

 

[LoLLess]

They probably just stuck a module in to show that it can boot. It's not uncommon for a "barebones" system to come without everything actually required to function properly. It's also not uncommon for computers to suppport larger modules than were offered originally. They double in size very couple years.
Memory needs to rest every few cycles to refresh. Multiple memory channels allow the RAM to keep working while other modules are "refreshing". Faster multicore CPUs need more channels to support their speed, and bandwidth.
Dual channel memory was last used in a workstaion on 4core 4 thread systems in the LGA775 era.
I'm not saying it doesn't work. Runs just fine in my $20 Optiplex 380.

ok cool so basically just buy 2 more sticks and it should be fine and stable? yea i only paid $50 for this 1 well worth imo

 

[clarkjd]

ok cool so basically just buy 2 more sticks and it should be fine and stable? yea i only paid $50 for this 1 well worth imo

When you get the new sticks, make sure that they match your existing sticks in EVERY specification. Getting un-matched ram to work together is problematical at best and impossible at worst. Sometimes, even the EXACT same brand, make,and model will not work together, especially if purchased at different times and vendors. Even the ram manufacturer will not support unmatched ram to work. They sell ram in matched sets for a reason.