[SOLVED] DDR4 RAM compatibility ?

[Loki1349]

I've got an Asus X99-Deluxe Motherboard running with an i7-5820K and Corsair Dominator Platinum 2x8GB 2666MHz RAM.
I was browsing Amazon looking for components to build a new system sometime in late summer when I stumbled on this RAM kit (DOMINATOR® PLATINUM RGB 32GB (2 x 16GB) DDR4 DRAM 3200MHz C16). It was a good deal, and I bought it, looking forward mostly to my new system which I was going to build, but I also thought it would be neat that I could use it on my current system while looking for the rest of the components.

So, when the RAM arrived, I put it on my X99 motherboard, the system booted normally at first but experienced some instability. When I restarted to check if there's a problem with XMP, the system wouldn't post and would be stuck in an endless restart loop. Using the MEMOK button or resetting CMOS wouldn't help. I reinstalled my old memory, cleared the bios and my computer runs fine again.

Now the question is:

1. Is the new RGB RAM kit I bought faulty and should I return it?
2. Is there a better chance that I'm being an idiot and my old Mobo/CPU simply aren't supported and the RAM is fine (manufacturer's website states it supports Intel 300 Series and newer)?

I always thought memory is memory and if it fits the slot (DDR4), it should work. But heck, x99 is old, and 16gb DIMMS weren't even supported at launch and came via a bios update.

UPDATE
Some new information came to light, adding it to the first post in order to make it more noticeable:

I tried the new DIMMs one at a time, at 2666Mhz. Both modules POSTed just fine separately, and performance in Windows (desktop performance, video games, Photoshop) was as usual with each individual RAM stick. So no complaints there.

Then, I went and installed them both at the same time, into the very same slots that use to hold my old DIMMs. When both new RAM sticks are installed, the system booted up normally, but weird stuff started happening with Windows performance, just like the very first time. I got unusually high CPU usage out of nowhere, and FPS in games plummeted into a slideshow.

Example of high CPU usage with both DIMMs from the new kit installed. Neither this nor other performance anomalies happen when the old kit or individual DIMMs from the new kit are installed separately.

Does anyone have a hint as to why the new RAM sticks work OK independently, but issues occur when BOTH are used? Is it the voltage? Is it the timings? Memory controller on an old mobo?
Is it safe to assume that the RAMs are ok and I'm good to keep them for a new system?

Thanks in advance, any hint or tip would be appreciated

 

[siaan312]

It's less that it's not supported, it's more that the memory controller, and traces on such old motherboards aren't really cut out for such high speeds (3200 isn't that fast, but cl16 and on 16gig sticks is pretty good, and much better than what they had in 2015/16)
If you just try to run at 2666 it should work.

You could probably also get 3200mhz to work, but that would require memory overclocking which is a chore, and doesn't do that much for these older chips in terms of performance.

 

[Loki1349]

When I tried to make it work, the BIOS wouldn't even load a lot of times. I did some more experimenting, I managed to load into Windows again two times, running at default 2133mhz, but it wasn't even stable at that speed. I also noticed that RGBs on one of the DIMMs would light up in all red while the system failed to POST. That's why I thought the RAM itself might be at fault.

I'm not primarily concerned with making it work with my current X99 mobo.
I'm rather interested in finding out whether there are any tell-tale signs that the new RAM I bought is DOA. If it is not, I'd gladly keep it and wait to install it into a new motherboard when I get it (looking for Ryzen7 5800x with either b550 or x570)

PS
All my friends either use Mac or Windows-based laptops, so I can't use any of their computers to test the memory. That's why I'm asking online

 

[smartmantech47]

Yeah Get amd these days, they smash intel in terms of value and performance. Anyways, if budget is not an option, then X570 is the way to go. The X570-Pro wifi from asus is a nice option, and for b550, the B550M-Wifi tuf gaming from asus is a solid option too.

 

[Loki1349]

Yeah Get amd these days, they smash intel in terms of value and performance. Anyways, if budget is not an option, then X570 is the way to go. The X570-Pro wifi from Asus is a nice option, and for b550, the B550M-Wifi tuf gaming from asus is a solid option too.

Yes, I was thinking in a similar direction. Prime X570-Pro seems to have availability issues, so I was looking for a ROG Strix X570-E Gaming.

 

[smartmantech47]

Okay then. Just get wifi with the motherboard if you're not using ethernet because it's a pain to install wifi

 

[Loki1349]

It's less that it's not supported, it's more that the memory controller, and traces on such old motherboards aren't really cut out for such high speeds (3200 isn't that fast, but cl16 and on 16gig sticks is pretty good, and much better than what they had in 2015/16)
If you just try to run at 2666 it should work.

You could probably also get 3200mhz to work, but that would require memory overclocking which is a chore, and doesn't do that much for these older chips in terms of performance.

So I couldn't sit idly, and I gave it another shot. I tried the new DIMMs one at a time, at 2666Mhz. Both modules POSTed just fine separately, and performance in Windows (desktop performance, video games, Photoshop) was as usual with each individual RAM stick. So no complaints there.

Then, I went and installed them BOTH at the same time, into the very same slots that use to hold my old DIMMs. When both new RAM sticks are installed, the system booted up normally, but weird stuff started happening with Windows performance, just like the very first time. I got unusually high CPU usage out of nowhere, and FPS in games plummeted into a slideshow.

Does anyone have a hint as to why the new RAM sticks work OK independently, but issues occur when BOTH are used? Is it the voltage? Is it the timings? Memory controller on an old mobo? Is it safe to assume that the RAMs are ok and I'm good to keep them for a new system?

Thanks in advance, any hint or tip would be appreciated

 

[Mr.Spock]

it's not necessarily the RAM itself, but what the bios determines to be "optimal" timings based on the SPD values it detects. a lot of times you can arrive at perfectly stable configurations setting the timings manually vs what the bios calculates when you default to "Auto" . Using XMP the bios just guesses, QVL lists are just RAM that's been tested to work - doesn't mean other versions will or won't.

 

[siaan312]

So I couldn't sit idly, and I gave it another shot. I tried the new DIMMs one at a time, at 2666Mhz. Both modules POSTed just fine separately, and performance in Windows (desktop performance, video games, Photoshop) was as usual with each individual RAM stick. So no complaints there.

Then, I went and installed them BOTH at the same time, into the very same slots that use to hold my old DIMMs. When both new RAM sticks are installed, the system booted up normally, but weird stuff started happening with Windows performance, just like the very first time. I got unusually high CPU usage out of nowhere, and FPS in games plummeted into a slideshow.

Does anyone have a hint as to why the new RAM sticks work OK independently, but issues occur when BOTH are used? Is it the voltage? Is it the timings? Memory controller on an old mobo? Is it safe to assume that the RAMs are ok and I'm good to keep them for a new system?

Thanks in advance, any hint or tip would be appreciated

Try running at 2133.
If it's still bugging out there, then it's either a ram DOA or a compatibility problem.
My reasoning is, I think the ram is fine, just, it's probably overloading your weak sauce 6/7 year old memory controller.

 

[Loki1349]

Try running at 2133.
If it's still bugging out there, then it's either a ram DOA or a compatibility problem.
My reasoning is, I think the ram is fine, just, it's probably overloading your weak sauce 6/7 year old memory controller.

Tried that sometime after writing my previous post. It refused to post @2133zMHz at all.
However after today's test and both modules working fine on their own, my intuition would be similar to yours, I think it's rather my motherboard showing its age than a RAM hardware issue. At this point, I'm leaning in favor of keeping the new purchase for future use.

Thanks a lot for your insights!

 

[Loki1349]

I'm pretty sure my RAM is in good condition at this point, so I consider the issue solved. But if you're bored and up for some curious stuff here you go:

So once the question was settled in my mind, I decided to try one last crazy idea, just for fun. I put my old 2666 Mhz 8GB Corsair Dominators into the primary slots and the new 3200 Mhz 16GB ones into secondaries for a quad-channel config. The BIOS loaded up the (old) 2666 XMP for all DIMMS automatically, so I left it at that. Windows booted up normally and, to my surprise, showed no sign of instability or impaired performance. It passed the CPU-Z quick benchmark with good results (for my old CPU), and successfully ran through a AIDA64 stress test (cpu+ram+gpu) while I was doing some work on my laptop. I booted up some games, and the FPS was where I expected it to be on a normal day.

I'm not sure what did the trick - forcing the old XMP (which was validated to work with my cpu/mobo combo) on the new RAM, or forcing the memory into a quad-channel config (maybe the memory controller was struggling to handle 32GB+ in dual-channel mode), but now suddenly I have a stable functioning system with 48GB of RAM Far from optimal, I know, and it may have its own issues, but it's remarkable that it worked at all.