Can you use two types of ram at the same time?

_Bata_

Reputable
Apr 18, 2015
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Hi, right now i have one kingston ram stick 4.00GB Single-Channel DDR3 @ 798MHz (11-11-11-28) RAM. And im just about to get some corsair vengeance 2x4gb ddr3 1600mhz dual channel. Initially i was planning to remove that kingston ram and only stay with the corsair memories. But right now i think that would be a waste of ram. What are the CONS of using these rams at the same time? i know they won't work on "dual channel" but i think that i've read somewhere that if you put slower ram with faster ram, the fastest one slows to match the other timings or something like that. I don't know if this is true but, is there any disadvantage at all?

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Edit: So what do you guys recommend me, 8gb 1600mhz ram or 12gb 798mhz ram?
 
Solution
Mixing speeds will work most of the time. However, it is considered best practices to install a matched set. What you should do is install your new 2x4 kit and take the one sick out. Also, just because that kit says it is dual channel didn't mean it will run that way. Your motherboard will decide if they run in dual channel mode. Check the motherboard specs...Populating a third slot may effectively DISABLE it's dual channel mode.

Unless you are doing something that requires more than 8 gig of RAM I would recommend you just install that 8 gig kit.

-Sent from my Galaxy S 6
Yes, it will run at the timing of the slowest chip and should be fine. SOMETIMES, motherboards are picky and they won't work, but that used to be more back in the SD, DDR1, DDR2 days of having to sit with a box of chips just to find a couple that work together. DDR3 is a lot more forgiving and I've mixed all kinds of combos.
 

DeadlyDays

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Mar 29, 2013
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yes, the ram will run at the speed of the slowest one. Also, you may have issues if the voltage requirements are different on each type. Like my old machine had ram that was rated for 2.1v, and another that was leik 1.8 or something. Mobo wouldn't boot because of it. The higher volt ram would only run with 2-2.2v, wouldn't boot without that much. So I had to overvolt my other ram and undervolt my high volt ram to try and bridge the gap just to boot. Then I underclocked the high volt ram so it'd run stable.

be careful of that.
 
Mixing speeds will work most of the time. However, it is considered best practices to install a matched set. What you should do is install your new 2x4 kit and take the one sick out. Also, just because that kit says it is dual channel didn't mean it will run that way. Your motherboard will decide if they run in dual channel mode. Check the motherboard specs...Populating a third slot may effectively DISABLE it's dual channel mode.

Unless you are doing something that requires more than 8 gig of RAM I would recommend you just install that 8 gig kit.

-Sent from my Galaxy S 6
 
Solution

Tradesman1

Legenda in Aeternum
What CPU, mobo and model numbers of the DRAM, if the rig is less than 4 years old when you see 798 it is prob the true freq of the DRAM and since this is DDR (DOUBLE data rate) you are running at 1600 effective.

and FYI as some bad info has been provided here:


Mixing DRAM can be and often is problematic - however if they do play together, saying they will only run at the slowest speed of the slowest stick is a myth, they can and will run at whatever you can get them to run at, have run three mismatched 1333 and 1600 sticks before at 1866 with little to no effort.

Also, again if the sticks will play and rig is with the last 3-4 years, the DRAM will most often work in what's called Flex mode (an Intel innovation) where you would have 8GB in dual channel and the odd 4GB running in single channel.

All these items and more are covered in my Faqs and Fiction article here:

http://www.tomshardware.com/answers/id-2741495/ddr3-faqs-fiction.html