Question RAM upgrade - speed vs quantity?

[sir_troy]

I just got a Dell Optiplex 7070 i5-9500.
It comes with 16gb of DDR4 2666MHz. I have a spare 16gb DDR4 2400MHz and 4gb of DDR4 2666MHz. Which one should I chuck in the extra slot?

 

[CountMike]

I just got a Dell Optiplex 7070 i5-9500.
It comes with 16gb of DDR4 2666MHz. I have a spare 16gb DDR4 2400MHz and 4gb of DDR4 2666MHz. Which one should I chuck in the extra slot?

Speed difference is negligible so 2x16GB would obviously be better if you can have them running together that is. Mixing RAM can mean big trouble and at best they would run at the speed of slower one or less and not even have them in dual channel which slows performance considerably. You'll just have to try each combo yourself.
I would rather sell them all and buy a proper kit of 2x16GB which is as fast as possible.

 

[sir_troy]

Speed difference is negligible so 2x16GB would obviously be better if you can have them running together that is. Mixing RAM can mean big trouble and at best they would run at the speed of slower one or less and not even have them in dual channel which slows performance considerably. You'll just have to try each combo yourself.
I would rather sell them all and buy a proper kit of 2x16GB which is as fast as possible.

Hi CountMike - thanks for the reply. Yeah I was aware of the speed drop - I guess the question should have been is it better to run 32GB of DDR4 at 2400MHz or 20GB of ram at 2666MHz (for fairly standard usage no hardcore gaming, mainly just for watching live streams/youtube/web browse on the TV)

 

[williamjeremiah]

Hi CountMike - thanks for the reply. Yeah I was aware of the speed drop - I guess the question should have been is it better to run 32GB of DDR4 at 2400MHz or 20GB of ram at 2666MHz (for fairly standard usage no hardcore gaming, mainly just for watching live streams/youtube/web browse on the TV)

32GB

 

[CountMike]

Hi CountMike - thanks for the reply. Yeah I was aware of the speed drop - I guess the question should have been is it better to run 32GB of DDR4 at 2400MHz or 20GB of ram at 2666MHz (for fairly standard usage no hardcore gaming, mainly just for watching live streams/youtube/web browse on the TV)

Don't have to ad much more, just to reiterate that frequency alone doesn't equal performance. There's also matter of latency ) look at Cl (Cas latency) as low as possible and specially dual channel configuration which yields 33-50% better memory performance than single channel (one RAM stick) and that would be very difficult to impossible to achieve with 2 different sticks. So in your case, if you are not willing to swap for a 2x16GB kit , it would make no difference performance wise whichever stick you ad. More RAM helps only if you are habitually running out of memory, otherwise none.

 

[Bob.B]

I just got a Dell Optiplex 7070 i5-9500.
It comes with 16gb of DDR4 2666MHz. I have a spare 16gb DDR4 2400MHz and 4gb of DDR4 2666MHz. Which one should I chuck in the extra slot?

Assuming the sticks will play nice together 16GB+4GB will give 8GB running dual channel and 12GB running single channel.

16GB+16GB will give 32GB running dual channel.

 

[artk2219]

I just got a Dell Optiplex 7070 i5-9500.
It comes with 16gb of DDR4 2666MHz. I have a spare 16gb DDR4 2400MHz and 4gb of DDR4 2666MHz. Which one should I chuck in the extra slot?

Capacity is always over speed, you can have the fastest RAM available, and it wont matter if there isn't enough of it.

 

[Karadjgne]

Relative timings over capacity and speed. I'd take 16Gb of 2666 cas18 over 32Gb of 3200 cas22 any day.

 

[Richj444]

Even if your normal usage required more than 16gb of Ram?