Is it ok to have RAM at different mhz?

[Harrygc00]

I have 2 sticks of DDR3 RAM, one at 1866 mhz and one at 1333 mhz.

Is this ok to have? (I have heard that it is OK but someone else told me that it isn't?)

 

[Dunlop0078]

It might be, only way to know for sure is to try it. Mixing ram that was not packaged together is hit or miss. If it does work the mobo will set both sticks to 1333mhz.

 

[atljsf]

you can do that but the slower ddr3 1333 will make the faster dd3 1866 will slow down to 1333

if timings or the ram itself is not cooperative, you might get stability issues or all could go well, but ideally mix speeds is not what one would like to do, sometimes the only thing that can be done, perhaps

 

[JackNaylorPE]

1. Buy RAM appropriate for your board

a. On a dual channel board, always by RAM in packages of 2 minimum, if you want more, buy 4 in same package
b. On a quad channel board, always by RAM in packages of 4 minimum, if you want more, buy 8 in same package
b. On a triple channel board, always by RAM in packages of 3 minimum, if you want more, buy 8 6n same package

2. Mixing RAM from separate packages is always a crap shoot, may work , may not but you have no guarantee is it doesn't. It very may be that the single RAM stick you buy may have been sold in a single package because it failed in in-house testing when paired with another stick.

3. You have more to worry about than speed, what about timings and voltages ? You will have to start my manually setting the speed, timing and voltage to the lowest common denominator ... lowest speed, highest timings, highest voltage. However, there are limits ... the 1st DDR3 sticks were 1.65 and these can be mixed with 1.5 ... but a 1.2 - 1.35 sticks I wouldn't mix w/ 1.65

 

[Harrygc00]

I have had the RAM installed in my PC for around 1 month now and it seems to be working fine? I originally did have 2 sticks of 1866 but one didn't work and I accidentally brought a stick of 1333 by mistake (first time building a PC, so a bit of a dumb mistake I know). According to Speccy the RAM is running at 665 mhz? Is this a problem?

Thanks for all the help so far .

(Sorry about the really late reply).

 

[JackNaylorPE]

DDR = Double Data Rate ... Double = 2 ... 2 x 666 = 1333

 

[Harrygc00]

DDR = Double Data Rate ... Double = 2 ... 2 x 666 = 1333

Sorry, I may be being a bit dumb here, but what would that mean?

 

[atljsf]

you asked the 665 mhz number, they explained

 

[Harrygc00]

you asked the 665 mhz number, they explained

Ah okay, thank you .