2x2 GB & 1x4 GB. Will they work fine together?

[Anoop Parwani]

Hi,

I have a 2x2 GB setup. I want to add another 4 GB but they dont have it anymore in 2x2 but they have it as 1x4 GB for the same brand and series (G-Skill Ripjaw)

Is that OK? Will everything work fine if I add a 1x4 GB stick with 2x2 GB sticks?

 

[dave_the_nerd]

It'll work fine. Any additional benefit you see from running RAM in dual-channel mode will go away when you're using that second 4 GBs of RAM, but you probably won't notice.

You do have a 64-bit OS, right?

 

[Anoop Parwani]

Good.

Yes im running Win 8 64 bit.

Now what if the 2x2 GB sticks have 1.65v mentioned on them and the 1x4 GB is at 1.5v?

Would this be a problem?

 

[dave_the_nerd]

Probably not. With any luck, the motherboard will simply run everything at 1.65v. It shouldn't damage your 1.5v RAM.

That said, if your motherboard decides to run everything at 1.5v, your 1.65v RAM may become unstable at its rated speed.

For simplicities sake, it's generally recommended to run all the same voltages whenever possible. Conversely, you don't need to worry about mixing brands.

 

[Insert_Nickname]

For simplicities sake, it's generally recommended to run all the same voltages whenever possible. Conversely, you don't need to worry about mixing brands.

If you have 4 DIMM slots available, check your current RAMs timings and voltage. Then get another 2x2GB set that matches those timings and voltage. Place one of your current DIMMs and one new DIMM in each of the two channels. Should work just fine, I have never experienced problems doing it that way.

 

[Anoop Parwani]

Which app tells me the current timings and voltage being pushed to the ram slots?

Can i set the voltage to 1.575 for both the 1.65v & 1.5v? should that work ok? Or what if i run both of them at 1.65v? wouldnt it be like OC for the 1.5?

Can we set different timings and voltages for each slot?

All ram modules that r out now all are 1.5v.

 

[Insert_Nickname]

Which app tells me the current timings and voltage being pushed to the ram slots?

I'd recommend either Aida64, SiSoft Sandra or HWinfo.

Can i set the voltage to 1.575 for both the 1.65v & 1.5v? should that work ok? Or what if i run both of them at 1.65v? wouldnt it be like OC for the 1.5?

Can we set different timings and voltages for each slot?

Wouldn't recommend trying that. Newer DDR3 memory is 1.5V or 1.35V (spec requires the RAM to tolerate 1.525V), not everything can handle 1.65V and you might fry something.

Some AMD boards allow you to set different timings for each channel. This is a serious case of YMMV.

 

[john3850]

I would always try to go with the larger size stick even if I had to use flex mode.
At the egg most 2x2 sticks average +55.and yet I see 2x4 going for $65-70 so for ten bucks more I can get double the amount.
When I built my 1366 I used 3x2 gskill pc 1600cas 7. but when I wanted more ram I used 3x4 pc-1600 c-9 rather then another 3x2 which saved me money plus I got double the amount.

 

[Insert_Nickname]

At the egg most 2x2 sticks average +55.and yet I see 2x4 going for $65-70 so for ten bucks more I can get double the amount.

Agree 100%.

If you can get double the capacity for $10 extra, its really a no-brainer. Nothing wrong with using Flex mode BTW. My point is only that you should make sure you have the same capacity on all memory channels. That way you do not need to use flex mode in the first place. Flex mode is only used if you have dissimilar capacities on each channel (f.x. one 2GB DIMM and one 4GB DIMM on channel A and one 2GB DIMM on channel B).

 

[Blue_Max]

It'll work fine. Any additional benefit you see from running RAM in dual-channel mode will go away when you're using that second 4 GBs of RAM, but you probably won't notice.

In the Intel world, that's no longer true! It's smart enough to go dual wherever it can. For example, if you had ONE 2GB module and one 4GB module, putting them both in channel "A" would mean the system runs dual-channel for the first 2+2GB, single-channel in the remaining 2GB.

In his case, straight from Intel; Dual-channel w/ 3 DIMMs:

 

[Insert_Nickname]

In the Intel world, that's no longer true! It's smart enough to go dual wherever it can. For example, if you had ONE 2GB module and one 4GB module, putting them both in channel "A" would mean the system runs dual-channel for the first 2+2GB, single-channel in the remaining 2GB.

Wasn't that more or less what I wrote? So long that you keep equal capacity on each channel, you can run dual channel. It doesn't matter how many DIMMs you use. 1x4GB and 2x2GB is just as valid for running dual channel as 2x4GB.

Slightly OT, but I did run 2x256MB and 1x512MB DIMMs in dual channel on my ten year old Athlon system. It had three DIMM slots, but worked just fine with that config.