[SOLVED] Can I use double sided memory (4GB DDR3) mixed with a single sided memory?

Aug 9, 2019
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Can I use double sided memory (4GB DDR3) with a single sided memory? The double sided memory are too expensive for me...And i want to get 8GB or why not 12GB
 
Solution
It's not really about one being double sided and one being single sided, as much as it is about the memory configuration consisting of mixed memory of ANY type that didn't come together in a kit. What are the speed and timing specs of both sticks, and what is your CPU and motherboard model numbers?

Here is my usual spiel on trying to use mixed memory, in general.




The odd man out, or, unmatched memory

While memory modules that did not come together in a matched set that was tested by the manufacturer to be compatible, certainly CAN still work together, often it does not. Right up front I'll tell you that if you are trying to get sticks to work in the same machine together that were purchased...
It's not really about one being double sided and one being single sided, as much as it is about the memory configuration consisting of mixed memory of ANY type that didn't come together in a kit. What are the speed and timing specs of both sticks, and what is your CPU and motherboard model numbers?

Here is my usual spiel on trying to use mixed memory, in general.




The odd man out, or, unmatched memory

While memory modules that did not come together in a matched set that was tested by the manufacturer to be compatible, certainly CAN still work together, often it does not. Right up front I'll tell you that if you are trying to get sticks to work in the same machine together that were purchased separately, even if they are otherwise identical according to the kit or model number or if they would seem to have identical timings and voltage requirements, there is a very good chance that you simply will not be able to do that. There is also a pretty fair chance that you might be able to if you are willing to take your time, listen to and understand what you are being told and follow the steps necessary to determining if they will "play nice" or not.

The exception in most cases will be that if the memory from both sets are the same speed and timings and both kits are within the JEDEC specifications for the default speed on that platform, so for example, 2666mhz on the latest Intel Z390 platform, 2133mhz on Ryzen first and second Gen platforms, then they stand a much better chance of working together but if they are higher speed kits the chances begin to diminish from what they might be at the low speed and loose timings end of the scale.

A word of advice. If you just purchased this memory, and for whatever reason you bought two separate sticks of the same memory instead of buying them together in a matched set, see if you can return them for a refund or credit towards buying a similar or same set of matched sticks that come together in a kit. It is ALWAYS better to have matched modules because from brand to brand, or even within the same brand, in fact, even when the part numbers are IDENTICAL, there can be anything from simply slightly different memory chips that were sourced from different bins at the end or beginning of a production run to entirely different configurations altogether even though the model numbers seem to be the same. Some manufacturers even reuse model numbers when they discontinue a product. Point being, memory is only the same for sure when all sticks came out of the same blister pack or packaging and were sold as a tested kit.

In order to determine if differences in the memory, or a need for increased voltage when using more than one stick (Especially if you are running three or more sticks) are responsible for the problems you are having you will always want to begin your troubleshooting process by attempting to boot the machine with only a single stick of memory installed. Also, for practically every consumer motherboard that's been sold since at least as far back as about 2014, the A2 memory slot which is the second slot over from the CPU socket, is THE slot that is most commonly designated for the installation of a single memory module. Slots A2 and B2 are almost always the slots specified in the motherboard memory population rules for use with two modules. If you need to install a third module I have no opinion on which of the remaining slots to use for that, but typically since the A1 slot is right next to the CPU socket and often interferes with the CPU cooler or fan, I'd say the B1 slot was probably just as good.

Honestly, I don't ever recommend that you HAVE three modules installed anyhow. Using memory in pairs is always a better option so that normal dual channel operation will occur. And that's another thing. When it comes to memory there are no "single channel" or "dual channel" memory modules. There are ONLY memory modules and the motherboard and CPU architecture will determine whether or not dual, triple or quad channel operation is possible based on the architecture and how many modules are in use. Occasionally though there are situations where it might make sense to run three modules and some boards CAN use three modules in a FLEX type mode where two of the modules will operate in dual channel while the third oddball module will run in single channel. I'd avoid oddball configurations though if possible because many motherboards will simply run ALL modules in single channel mode when an odd number of modules are installed.

If you think you will ever need 16GB of memory, then buy 16GB of memory from the start so you can get it all in a matched set that has been tested, and eliminate a lot of problems right from the start.
 
Solution
Aug 9, 2019
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1
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CPU: Intel Core i5 2320 3.00 ghz
GPU: GTX 550 Ti
Motherboard: Acer Predator G3610
RAM: 4GB DDR3 1333 mHz ; CL9 ; running at 1.5V ; and i've got 3 slots free, where i want to buy a 8GB kit, but i don't know if they need to be double side or single side, my memory is double sided..
 
Download CPU-Z. Install it. Run it. Click on the SPD tab.

Right below where it says "Memory slot selection" you need to select the DIMM slot your memory is installed in. Once selected it will bring up the specs for your installed memory module. Find the field where it says "Part number" and post the model of your memory module here.
 

Moza805

Honorable
Aug 17, 2014
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You'd be best getting an 8GB kit and removing the 4GB set that is in there. This is because the RAM sticks should be matched to avoid system instability.

All manufacturers worth their salt do this with all kits they sell.
 
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Moza805

Honorable
Aug 17, 2014
7
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10,525
So in your situation the answer is maybe, but probably not. You need to get a set of memory that is rated to work together.

It doesn't appear to matter whether the memory is double or single sided (assuming you mean memory chips on both sides of the RAM board).

The factor that determines whether your memory modules will all work together is more to do with ensuring that they are all the same - that is to say same manufacturer, same model, same size, speed etc. Even better if they are from the same manufacturing run.

You can take the risk with a new 8GB kit running alongside your current 4GB kit but it is likely to be unstable :(

In your situation I would suggest buying a new 8GB kit, trying to run it alongside the 4GB kit. If it doesn't work, you can always take out the 4GB kit.

Further info available here: https://forums.tomshardware.com/thr...-and-i5-2500k-processor.2370837/post-15640007
 

fadingfool

Distinguished
Feb 11, 2010
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YMMV but earlier this year I dropped 2x8GB sticks (non-matched set) into my alienware area 51 to take my total ram up to 32GBs. The pre-installed RAM was rated at 2666 (non XMP) and the newsticks were 2400 but with 2666 as one of the XMP profiles. Cl 18 and cl16 respectively. All running fine at 2666 Cl 18 - no instability. I have also upgraded my laptop with an extra 8GB stick and all is fine (same speed and latency timings this time though - different make). I knew I was taking a chance but the cost difference was over double to get a matched pair at the time (and it was probably still worth it if I just ended up swapping out the old memory and have tighter timings).
 
Here's the thing. If your memory is below the threshold for JEDEC standards, which is generally 2666mhz for DDR4 or 1600mhz for DDR3, then it stands a good chance of running fine together when using mixed memory although there is ALWAYS some chance it will not based on factors. Those factors include how far apart the sticks are in terms of speed, number of chips, number of sides that are populated with chips, how different the timings are, what IC's are used (Memory chips) and also what motherboard and CPU are being used. Some memory controllers or board configurations are more forgiving than others.

The more "factors" you have that deviate from the original stick or sticks, the more likely it becomes that they will not play nice together. Keep in mind that even memory which is the EXACT SAME part number may not work together if it wsa not purchased together due to differences that might exist in any of the above factors from production run to production run. Often, three entirely different memory modules, based on configuration, could all share the same part number or you could have a set of 8 sticks that DID come together and yet still one of them refused to like the others.