Dual Channel vs Single channel memory upgrade: Dell Server

[sr2002]

I have a Dell C226 + Xeon E3-1225v3 based server with 4 memory uDIMMs.

The server came with a stock Hynix ECC Low Voltage DDR3 memory.
I added an addition 8GB Crucial Non-ECC + 1.5v module along side the stock memory and it seems to work (memory tests passed. The stock hynix is dual voltage 1.35/1.5) and I'm assuming both are running at 1.5v right now.

I wish to add another 8gb crucial stick, will having 8+8+4 sticks enable dual channel mode? Or will I need to have 8+8+4+4 or just 8+8 in order run in dual channel ?

Are there any significant gains with Dual channel? (I'd hate to throw away the stock 4gb stick 🙁 ).

Secondly, does a motherboard that claims to work with 1.35v memory with 32gb support, able to handle 32gb of 1.5v memory? Or would there be any problem with power consumption?

 

[06yfz450ridr]

you can mix an ecc with a non ecc? I thought that wasnt possible? if you are hitting the limit on your memory you will gain more performance from having more memory, I had a single 2 gig ddr3 stick lyng around that i threw in my rig now it is in single channel with 10Gb and I haven't seen any noticeable difference.
if this server is running vm it would be better with more memory and dual channel

 

[InvalidError]

To run in symmetrical dual-channel mode, both memory channels must have identical memory configurations.

Performance-wise, how much of a benefit there might be between symmetrical and interleaved memory channels depends on the software you are running. It can be anywhere from 0% to over 20%.

 

[InvalidError]

you can mix an ecc with a non ecc? I thought that wasnt possible?

You can. Simply turn off ECC in the BIOS so the CPU won't check ECC and get false positives on non-ECC DIMMs.

ECC DIMMs are exactly the same as non-ECC, they just have an extra DRAM chip or two to provide the ECC bits.

 

[sr2002]

I see. That's very good advice. So basically if I do 4+4+8+8, only then it will run in dual channel.
I guess I might just buy one more 8gb stick and do the 4+8+8, i dunno if its worth spending too much money on the ddr3 setup since most of the newer machines have started using DDR4.
Do you think 20Gb should be good enough for most games/2-3 VMs running on Vbox?

I bought this server for a very cheap price and it came with E3-1225v3 + 4gb ECC + 1tb Seagate blue (300$ shipped and with tax), I might upgrade later on to a 1231v3 from the current 1225v3 for the added HT. I'm using it for currently for gaming, and for VMs. I'm using Vbox for VM generation on Windows which is not the most efficient way as compared to bare metal KVM/ESXI. But using bare metal will mean I'll have to use the server exclusively for virtualization and no gaming.

 

[InvalidError]

Most games are happy enough with 8GB but personally, I prefer 16GB since that leaves all frequently accessed game files in the OS' disk cache and eliminates most HDD accesses after the initial load. With 20GB, there should be a fair amount to spare for VMs.

One word of caution about mixing DIMMs: the more different DIMMs you put in, the greater your chances of having compatibility and possibly stability issues. If you tried getting a single 4GB DIMM to pair with your existing ECC DIMM, it could be a long shot.