4 slots, 4 ram sticks, two different types of ram? Options

[smakme7757]

Interesting question i came across today on a norwegian board.

A guy has two ram sticks in his 4 slot mobo. They are corsair value ram (2*2). He wants to buy a set of kingston hyperX with the same specifications (2*2) so he will then have 8GB of ram and 4 slots filled. I said he's better off just buying an 8GB kit because problems can arrise when mixing different manufacturers ram.

A moderator then chimed and and said he believed it will be ok seeing as both sets of ram will be run as a pair and each are independant of each other?

Is that corerct? I'd never thought of that (Lots of stuff i don't think abought though lol)

This post has been edited by smakme7757: Aug 8 2011, 11:43 PM

[Dasa]

normally its ok to throw in 4 different brands of ram and it will work just fine but then sometimes things can go so wrong that even one stick of ram wont work in one mb but works fine in the next

your option of 2x4g is probably the safest and least likely to play up but both should work
and with 2x4g if it works together he could have 12g ram if not he still has 8g

[NukeJockey]

Interesting, I've never thought about it like that Smakme, because they're on seperate channels do they run independantly of each other?

Not sure tbh, I was under the impression that they had to be running the same timings etc. though.

[smakme7757]

normally its ok to throw in 4 different brands of ram and it will work just fine but then sometimes things can go so wrong that even one stick of ram wont work in one mb but works fine in the next

your option of 2x4g is probably the safest and least likely to play up but both should work
and with 2x4g if it works together he could have 12g ram if not he still has 8g

Well he had 2*2 (4GB) from before and wants to add another 2*2 for a total of 8. But yea i always prefer to buy a new kit and have everything the same. I had tremendouse trouble with me 2*2 and 2*1 kits of dominators which always acted up.

Interesting, I've never thought about it like that Smakme, because they're on seperate channels do they run independantly of each other?

Not sure tbh, I was under the impression that they had to be running the same timings etc. though.

Indeed, that's what sort of caught me off guard. I'd say that they would still have to be the same specs, but the whoe independancy thing was something new.

[fajw]

I tried to mix different DDR RAM but it didn't work.

[smakme7757]

I tried to mix different DDR RAM but it didn't work.

Thats was my experience as well. I had 2*2GB Dominators and 2*1GB Dominators of the same specs each on their own channel and it just caused problems.

It seems it works sometimes and not other times. I still say it's best to have matching sticks from the same kit.

[nobody813]

I'm using 2 slightly different types of 2x2GB DDR2 Patriot kits in my machine

And my server has 4x1GB DDR400 in a mixture of Kingston and Amicroe, and it works fine

Not saying it will work, but it's just a case of trial and error

[A Hitman]

I have 2x1GB and 2x2GB sticks from the same manufacturer in my computer and it hasn't caused any problems.
Each channel has a 1GB and a 2GB stick.

[UberPenguin]

My 790X was running 4 gig (2x2) of hyperx 1000mhz and 2 gig (2x1) of geil 800mhz both clocked to 1000mhz(DDR2) and there was never a problem. It used to be a more common problem when dual channel mode first came out but now it seems either the general quality of ram is better or the controllers are more robust.

Here's what intel has to say about it

Rules to enable dual channel mode
To achieve dual channel mode, the following conditions must be met:

Matched DIMM configuration in each channel
Same density (128 MB, 256 MB, 512 MB, etc.)
Matched in both Channel A and Channel B memory channels
Populate symmetrical memory slots (Slot 0 or Slot 1)

Configurations that do not match the above conditions revert to Single Channel mode.

The following conditions do not need to be met:

Same brand
Same timing specifications
Same DDR speed

Memory channel speed is decided by the slowest DIMM module populated in the system.

as taken from http://www.intel.com/support/motherboards/...011965.htm#dual

This post has been edited by UberPenguin: Aug 10 2011, 08:25 AM

[harhis23]

It would normally work. I remember my old P4, I combined 2 DDR with 2 SDRam. Still alive til today, though I'm not using it anymore.

[nobodyishere]

It depends on each motherboards memory implementation, you can mix all 4 slots with different speeds/timings and it should default to single channel mode, however if the board doesn't detect that all 4 are different, and assumes all 4 are identical without verifying (a corner that can be cut to reduce boot times), it may try to run them in dual channel mode with interleaving across the dimms, thats when you can run into a Madrid of problems/performance issues if they aren't all the same specs (although its rare, hence in 99% of manuals, it recommends to use identical size dimms in channels A+B or A/B+C/D to get maxium performance and compatibility).

[Dasa]

different speed\timming ram should still work together in dual chanel it should just all be set to the speed of the slowest stick by the mb
different size sticks i think need to be paired 2x1g and 2x2g so that dual chanel still works
if you had a 1g and 2g stick together i think it should then run single chanel
the above is in an ideal world when the odd wied compatibility problem dosent happen but it can and dose