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8 gb RAM 2 vs 3

Owe812

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Nov 18, 2021
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I am wanting to buy my son some RAM for his gaming PC. I have read that the PC works better with two cards vs one. It currently has 8 GB Ram using one card and I was wanting to find out if 2 would actually be better than 3
 
Yes, 2 sticks are better than 3. Get 1 more stick of 8GB and You are good to go.
 
It's better to get him 2 matching 8GB RAM sticks in a kit to make sure they will work together with less chance of issues. If he wants to re-use his old 8GB mis-matched stick, he can try adding it and see what happens. The 3rd stick won't really hurt performance if it works with the other 2, it might cause some compatibility issues though.
 
The more sticks you add the less chance of them running at similar (or same) timings, the ones in a kit (of 2, 3 or 4) will generally work fine. Higher density sticks though also provide better performance.
 
If he has 4 slots, you can use 2x 4GB in one channel, old 1x8GB in the other, to give 16GB and it will run all 16GB in dual channel mode.

If you have 3 that are 8GB then you'll have 16GB in dual channel and 8GB in single channel, not ideal.

The safest is just to buy a 16GB kit (2x8) that is in the QVL and sell the remaining stick.

Be careful if this is an OEM system, since some of them lock down the BIOS and you can't change anything, including frequency and voltage. If that's the case, gaming memory can leave you worst speeds than 'value' memory.
 
If he has 4 slots, you can use 2x 4GB in one channel, old 1x8GB in the other, to give 16GB and it will run all 16GB in dual channel mode.
Maybe. It depends on the motherboard/chipset.

There are all kinds of if this and if that. Until we know the specific motherboard, it is all speculation - with some simply being wrong.

I say we wait until the OP comes back with the motherboard model number.
 
It's better to get him 2 matching 8GB RAM sticks in a kit to make sure they will work together with less chance of issues. If he wants to re-use his old 8GB mis-matched stick, he can try adding it and see what happens. The 3rd stick won't really hurt performance if it works with the other 2, it might cause some compatibility issues though.
Askew on all three cards are exactly the same the same MHz the same gb the same amount of pins. Would it be better to have two of the same kind or three of the same kind same specs ?
 
Askew on all three cards are exactly the same the same MHz the same gb the same amount of pins. Would it be better to have two of the same kind or three of the same kind same specs ?
:( Once again - it depends on the motherboard! And you have yet to tell us which motherboard!

That said, it is always better (in terms of ensuring full compatibility) to have all identical sticks.
 
I'm going to echo what @Bill_Bright said. Buy a new set of match memory. I never personally seen or heard of 2x4+8GB working in dual channel. Generally it will boot at the lowest possible JEDEC and run in single channel mode. That is almost worst than one DIMM. Unless of course the applications requires 16GB, which means you have no other choice. If you live in the states, 16GB is like $40 on sale. Even cheaper used.
 
I'm going to echo what @Bill_Bright said. Buy a new set of match memory. I never personally seen or heard of 2x4+8GB working in dual channel. Generally it will boot at the lowest possible JEDEC and run in single channel mode. That is almost worst than one DIMM. Unless of course the applications requires 16GB, which means you have no other choice. If you live in the states, 16GB is like $40 on sale. Even cheaper used.

I wouldn't recommend it if there's a choice, but it does work.

This is copied from an Asus 10th gen manual (I checked and they copy-pasted it for the Ryzen equivalent too):
"You may install varying memory sizes in Channel A and Channel B. The system maps the total size of the lower-sized channel for the dual-channel configuration. Any excess memory from the higher-sized channel is then mapped for single-channel operation."

Like Bill said though, we really need the motherboard model to make sure it's accurate.
 
but it does work.
But note your second quote where it clearly states the excess memory is mapped for single channel.

So, if 2 x 4GB plus 1 x 8G is used the 2 x 4 will run in dual-channel and the 1 x 8GB will run in single. But it should be noted that is NOT a bad thing. 16GB is still better than 8, even if some is not as quick as the other. Windows will know how to manage it effectively.
 
But note your second quote where it clearly states the excess memory is mapped for single channel.

So, if 2 x 4GB plus 1 x 8G is used the 2 x 4 will run in dual-channel and the 1 x 8GB will run in single. But it should be noted that is NOT a bad thing. 16GB is still better than 8, even if some is not as quick as the other. Windows will know how to manage it effectively.

There's no excess memory in this configuration. The 2x4 would be one channel and mapped as 8GB, the 1x8 would be one channel and mapped as 8GB. This does assume that they are placed in the appropriate slots and 4 slots are available.

If there are 3x8 then the excess memory would be 8GB (because one channel has 16GB, one has 8GB) and that excess would run in single channel.
 
I'm going to echo what @Bill_Bright said. Buy a new set of match memory. I never personally seen or heard of 2x4+8GB working in dual channel. Generally it will boot at the lowest possible JEDEC and run in single channel mode. That is almost worst than one DIMM. Unless of course the applications requires 16GB, which means you have no other choice. If you live in the states, 16GB is like $40 on sale. Even cheaper used.
I've never used it personally, but I've heard people talk about this as a "Hybrid Mode". Intel calls it "Flex Mode", here: https://www.intel.com/content/www/us/en/support/articles/000005657/boards-and-kits.html#flex
 
:( Once again - it depends on the motherboard! And you have yet to tell us which motherboard!

That said, it is always better (in terms of ensuring full compatibility) to have all identical sticks.
To be honest this is a present for my son for his birthday and I can't really get to his computer find out exactly what motherboard I know it's an AMD processor but I'm not sure which one. I just know he requested more RAM because he's having issues with his gaming PC and I was going to try to surprise him.
Thanks for the help in the info.
 
I've never used it personally, but I've heard people talk about this as a "Hybrid Mode". Intel calls it "Flex Mode", here: https://www.intel.com/content/www/us/en/support/articles/000005657/boards-and-kits.html#flex
Assuming the right slots are used, then it would just be dual channel mode, flex mode would apply if one channel was filled with 1x4G+1x8G and one channel was 1x4G (8GB excess from the 8GB stick).

To be honest this is a present for my son for his birthday and I can't really get to his computer find out exactly what motherboard I know it's an AMD processor but I'm not sure which one. I just know he requested more RAM because he's having issues with his gaming PC and I was going to try to surprise him.
Thanks for the help in the info.
A screenshot from cpu-z would be enough, could you disguise it as 'troubleshooting'?.
 
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yeah, we would like to have some more info before recommending anything :)
 
Making assumptions here, I'd say it is DDR4 Ram so get 16GB of 3600MHz Ram (2 * 8GB sticks) and make sure the Cas latency is an even number, The part number should include C16 or C18 towards the end.
Even if he uses his existing ram all three sticks will still run in Dual Channel and at the speed of the slowest stick of Ram.
 
you can have dual channel with 3 sticks if you follow the rules

 
There's no excess memory in this configuration. The 2x4 would be one channel and mapped as 8GB, the 1x8 would be one channel and mapped as 8GB. This does assume that they are placed in the appropriate slots and 4 slots are available.
Once again, maybe. It depends on the motherboard. Not all dual-channel boards configure 3 sticks in the same manner.
you can have dual channel with 3 sticks if you follow the rules
:( That link specifically deals with "Intel Desktop Boards". Nothing there says all boards based on Intels behave the same way. But it does not matter. The OP has said it is an AMD based board.

@Owe812 - Since you don't know which board he has, I recommend, when you get a chance, you get on his machine and visit the Crucial Memory Advisor. Run the scanner and it will tell you what RAM is compatible with that board. If you buy directly from Crucial suggested RAM they will even guarantee compatibility. Typically their prices are very competitive but just 2 months ago, I bought new RAM for my laptop and it was even $10 cheaper than Amazon. :) And shipping was free too.

If this is a factory built computer from Dell, HP, etc., you should be able to get the exact model number from the back of the computer. And then plug that information manually in the Memory Advisory - though to me, the scanner is better.

Other RAM makers have similar wizards but it is hard to go wrong with Crucial. I have never had a problem with it working with other brands.
 
Once again, maybe. It depends on the motherboard. Not all dual-channel boards configure 3 sticks in the same manner.

:( That link specifically deals with "Intel Desktop Boards". Nothing there says all boards based on Intels behave the same way. But it does not matter. The OP has said it is an AMD based board.

@Owe812 - Since you don't know which board he has, I recommend, when you get a chance, you get on his machine and visit the Crucial Memory Advisor. Run the scanner and it will tell you what RAM is compatible with that board. If you buy directly from Crucial suggested RAM they will even guarantee compatibility. Typically their prices are very competitive but just 2 months ago, I bought new RAM for my laptop and it was even $10 cheaper than Amazon. :) And shipping was free too.

If this is a factory built computer from Dell, HP, etc., you should be able to get the exact model number from the back of the computer. And then plug that information manually in the Memory Advisory - though to me, the scanner is better.

Other RAM makers have similar wizards but it is hard to go wrong with Crucial. I have never had a problem with it working with other brands.
Thanks for the link where to buy the ram you've been a great help.
 
:( That link specifically deals with "Intel Desktop Boards". Nothing there says all boards based on Intels behave the same way. But it does not matter. The OP has said it is an AMD based board.
it's the same thing for amd
 
Thanks for the link where to buy the ram you've been a great help.
Good luck and keep us posted.

it's the same thing for amd
No it's not! Not for every board out there! So please stop saying all boards handle an odd number of sticks the same way. It just is NOT true. Saying it does is NOT helping the OP.

Newer boards are certainly better at this, but at this point, we have no clue how old this systems is - let alone the brand or model number of the board.

The fact is, some boards, particularly older boards required matched "pairs" of sticks, that is, an even number of sticks, to enable dual channel with the entire complement of RAM.
 
Good luck and keep us posted.


No it's not! Not for every board out there! So please stop saying all boards handle an odd number of sticks the same way. It just is NOT true. Saying it does is NOT helping the OP.

Newer boards are certainly better at this, but at this point, we have no clue how old this systems is - let alone the brand or model number of the board.

The fact is, some boards, particularly older boards required matched "pairs" of sticks, that is, an even number of sticks, to enable dual channel with the entire complement of RAM.

I never once said it's like that for all boards ever made. I said it worked because someone said otherwise. Then you questioned if it worked for AMD because the document was for Intel, and i said yes.
Deep breathes and read what someone writes before going all crazy like that.

Anyway if the system is that old having 16GB will probably help with nothing and the "issues" have nothing to do with RAM. I would actually bet my money that it has nothing to do with RAM, but that's another story.

What issues are and what system is would probably go along way to really help him, i agree with you on that one.
 
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