RAM question

[sybertiger]

i been thinking
is there a down side on runing
ram like this

4x8x4x8 (24gb)
or
4x4x8x8

will it slow down on a way or is the more usal combo better?

4x4x4x4(16gb)


same ram same speed just diffrent size sticks,
wondering if there will be a preformance inpact by mixing ram sizes

 

[Nether]

OK, so ive experienced some wierd configs before, so I'm just gonna use my example:

If you have a 2GB and a 4GB sticks available, some systems will still use them in Duel Channel (that what you really want?)

Addressable ram would be 6GB, but, only 4GB of this will be in duel channel on the memory controller.

Basically the system is only using half (2GB) of the 4GB stick in duel channel mode.

If data is stored in the non-duel channel ram (the remain 2GB), that data will be accessed slower than the rest.

I hope this helps you figure out the perfect configuration.

 

[sajunky]

Read m/b manual, they tell you which configuration is optimal. Generally it is optimal if your 2x4MB RAM sticks can work in dual channel as well as 2x8MB, but allocation to the slots depends on particular mobo.

 

[Pada]

Typically the motherboard RAM slots are dual channel in the following config: A1 B1 - A2 B2
So then you install it like: 8GB 4GB - 8GB 4GB <- like you've described in your first option.

No matter how you have the configuration, having more RAM will be more beneficial than having faster or better placed RAM.

For compatibility reasons, make sure that the voltage, frequencies and clock latencies are the same.
The voltage is the most important - the BIOS should pick the slowest one between the latencies and frequency if the modules don't match up

 

[Swa]

Assuming it's installed so as to still be running in dual channel both configurations are equally optimal.

 

[AlexGouws]

They're both fine configurations. Just as long as all of their frequencies match you won't have a problem with speeds!

 

[sajunky]

The most important for working in dual channel are two factors to match:

1. Size
2. Configuration (number of ranks). Sometimes marked on the module R1 or R2.

Missmatched ranks will never work in dual channel, even there are the same speed.
Different speed or timings is not critical, as BIOS will adjust to the slower one.