View Full Version : ROG Rampage Extreme V Corsair LPX RAM Issue

12-03-2016, 12:29 PM
Hey fellow ROG fans...

Potentially silly question, but I have had some serious issues trying to get my RAM working correctly. I have 8 x 4 GB Corsair Vengeance LPX DDR4 3000 (CMK16X4M4B3000C15), 4 x Red and 4 x Black, obviously 32GB total. The Red I have use Hynix IC's and the Black use Samsung IC's, but run at identical timings/latency/voltage.

But in looking at the current QVL it says that model RAM is supported BUT the right hand side of the QVL table which says DIMM Socket Support with option, gives options for 2/4/8.

Now for that RAM it has the options of 2 & 4 selected but not 8. So that would seem to mean that it does not like a full population of that RAM (i.e. 8 sockets being used). This would make sense given that I can never get any more than 4 of them working.

4 x Red work fine by themselves, OR 4 x Black works fine by themselves, so 16 GB. Put them together in same channels etc and it is not happy. The rare successful boot I had with all bays populated only showed 4GB total RAM.

So do I assume that that info in the QVL telling me that 8 of that DIMM just will not work? Or am I misunderstanding what looks like a pretty simple answer?

Would appreciate some verification before going out and buying some RAM that the QVL likes that has the settings I like and I can get more than 16 GB.

Not that it should matter in this case but PC details are; ASUS ROG Rampage Extreme V, Intel i7-5930, XFX 295X2 x2 (only 1 plugged in atm), and the mentioned Corsair Vengeance LPX DDR4 3000 RAM 32GB total - only 16 GB can be installed, Corsair AX1500i PSU



12-03-2016, 01:24 PM
By what you're saying, you probably bought two kits of memory for aesthetic purposes. From a hardware perspective, it's not the best thing to do. Raja has written a very detailed article about it here: Don’t combine memory kits! The meat and potatoes overview (https://rog.asus.com/forum/showthread.php?57038-Don%92t-combine-memory-kits!-The-meat-and-potatoes-overview)

12-03-2016, 02:33 PM
My theory was they were both same brand, timing, specs and product number!!!

Problem is though it seems that the board wont take 8 of the 4gb modules anyway.

Thanks for the article info though, much appreciated.

12-03-2016, 03:06 PM
So your system isn't picking up all your memory modules even at stock defaults (2133MHz)?

12-03-2016, 04:35 PM
No ... If I use one set or the other (bearing in mind both are same Corsair product/part number, but one is red the other is black) - however upon closer examination one is Hynix and the other Samsung IC's.

So if I use either red or black no problem. If I try and use them together in any combination or setting, then no go.

The closest I had to success was with all installed, but the system only seeing 4 GB, and that was with XMP enabled and at correct DDR4 3000.

It is incredibly strange, even though they use the same timings and voltage and are the same Corsair part for all intents and purposes, they just will not work together no matter what.

It's incredibly frustrating and bloody annoying to have wasted money. I know cosmetic is not the right way to go, but when it's the same part, all I expected was that the aluminium heat spreader was a different colour and everything else would be fine. Just the fact they use different IC's should not even be a problem.


12-03-2016, 06:39 PM
Manufacturers change chip brand without notice depending on availability and price, contact Corsair to see if they'll give you a replacement kit
The chances of a 2 kits working together are slim as it is, 2 kits with different modules is just not going to work well if at all

12-04-2016, 02:01 AM
Yep, you're right I'll contact them and see how I go ... I just did not have any faith they would do anything about it so I did not bother ....
Will let you know how I go

Thanks for your suggestions