Any downsides to mix+matching RAM modules

[Raintech]

Working on a new build right now, bought a new kit of RAM already, but realised I could Frankenstein up a bunch of older components from other builds that I'm not using anymore. More specifically, wondering what would happen if i mixed + matched different RAM kits with varying speeds/brands

 

For example, if my Motherboard had 8 memory slots, all in dual channel, it'd look something like this

Channel A(slot #1 and #5): My new Corsair Veangeance 2x 8gb 3000mhz RAM kit
Channel B(slot #2 and #6): Older 2x8gb Gskill Trident 2x 8gb 2444 mhz RAM kit
Channel C(slot #3 and #7): REALLY old 2x 4gb Gskil Ripjaws (not even sure what speed they are)
Channel D(slot #4 and #8): empty

I could probably leave the old 2x4gb gskill ripjaws out completely, but wondering how the Corsair Veangeance 3000 and the Gskill Trident 2444's would work together for example

Do the faster modules slow down to match the slower modules?
Will doing something like this cause possible instability? BSOD/memory crashes etc?

[Herman Mcpootis]

worst case scenario your motherboard freaks out and doesn't POST, but usually it'll just run at the fastest speed all ram sticks support. Dual/quad channel might be disabled too in some cases.

[TukangUsapEmenq]

9 minutes ago, Raintech said:

Do the faster modules slow down to match the slower modules?

This. Is a yes.

It will run on the slowest maximum speed of all module that you install.

 

Ex. Corsair 3000, mixed up with Gskill Trident 2444. All of it will run on 2444.

And if that Gskill Ripjaw got the more lower max speed, it will follow.

 

Suggesting using HWInfo for checking the max speed, tho. Then set all of the RAM on UEFI on that speed.

 

9 minutes ago, Raintech said:

 Will doing something like this cause possible instability? BSOD/memory crashes etc?

I'm mixing two brands here (Micron and TeamGroup) and it barely gone (only happens for 2-3 times in this lifetime of laptop, which about 2 years) for BSOD.

 

Point is, still stable af.

 

 

 

But tbh dunno on your case. It's two brand (and three models) of mix.

Might all of the three CAS latencies are different for each other, and might got some instability.

 

Best case, just test it. Get experiment from it. And yes as @Herman Mcpootis just said, if it does't POST, it doesn't work.

[Raintech]

9 minutes ago, dhannemon13 said:

Ex. Corsair 3000, mixed up with Gskill Trident 2444. All of it will run on 2444.

And if that Gskill Ripjaw got the more lower max speed, it will follow.

 

Suggesting using HWInfo for checking the max speed, tho. Then set all of the RAM on UEFI on that speed.

Alright, this was exactly what i was looking for, cheers.

Doesn't hurt to try it out i suppose, end of the day 16gb RAM is still probably plenty anyways, but sticking in 32 means i won't need to worry about it ever again for the forseeable future