AORUS RGB Memory DDR4 16GB (2x8GB) 4400MHz isn't detecting

Joined
Aug 9, 2022
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I've bought Z690 TOMAHAWK WIFI DDR4,
Processor: Intel Core i5-12600K
Crucial MX500 1TB SATA SSD (Windows 11 is already installed on this)
For this system i bought AORUS RGB Memory DDR4 16GB (2x8GB) 4400MHz RAM. Installed in 2 and 4 slots. But, it is not booting into the system. Going into the BIOS automatically there under memory section Under model it is showing as Unknown. Am I wasted money on an incompatible RAM? Is there anything to make it work? Updated bios to latest but the same problem persist.
 

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citay

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Oct 12, 2016
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That "Unknown" has no relevance, i don't even see that screen, because i immediately set my BIOS to Advanced View (press F7). I don't think it will affect anything.
Your XMP is potentially difficult to run, no matter if your RAM model was listed there or not.

The more important question is, why get such a kit, with a CPU where the IMC (memory controller) needs a divider (Gear2 mode) for high RAM speeds?
See my thread RAM explained: Why two modules are better than four / single- vs. dual-rank / stability testing under 4).

As i explain there, such kits become mostly useless with 11th gen and 12th gen CPUs, because of the necessary divider for the IMC, and because those high RAM speeds are quite challenging to reach. On top of that, the BIOS of the 600-series had lots of problems with some XMP profiles, which are slowly being solved. But DDR4-4400 is a very demanding XMP profile. XMP is never a guarantee, it's only a goal that can be reached in optimal conditions. So about the RAM speed that's on the packaging, you can buy RAM with whatever advertised speed that you want, but that only means that the RAM itself is capable of it. However, the following factors all affect if the RAM can run at a certain speed:

- Your mainboard (PCB layer count, PCB trace optimization, RAM slot layout, component selection, RAM VRM etc.)
- The mainboard's BIOS optimizations
- Your CPU's integrated memory controller (IMC), quality depends on the individual CPU (silicon lottery, not only for CPU core quality, also for Uncore/IMC quality)
- And in the end, the properties of the RAM modules.

So yes, in a way, you wasted money, because a) it won't be faster than a DDR4-3600 kit with nice timings, and b) your memory system has difficulty to run such a demanding XMP profile.
Everything above DDR4-4000 may require manual tuning to make it work, it's extreme territory. It doesn't matter how good the RAM is on its own. Your CPU, board and BIOS have to be able to do it.

At DDR4-4400 CL19-26-26-46, your kit has absolute latencies of:
tCL = 19 clocks = 8.64 ns (at 4400)
tRCD = 26 clocks = 11.81 ns
tRP = 26 clocks = 11.81 ns
tRAS = 46 clocks = 20.91 ns

However, due to it requiring Gear2 mode for the IMC, it can add another 5+ ns!

Let's look at a kit of DDR4-3600 CL16-16-16-36 (G.Skill F4-3600C16D-16GVK for example) then:
tCL = 16 clocks = 8.89 ns (at 3600)
tRCD = 16 clocks = 8.89 ns
tRP = 16 clocks = 8.89 ns
tRAS = 36 clocks = 20 ns

Not bad, this kind of XMP profile will probably make no problems, and it can still easily run in Gear1 mode.
 

RemusM

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Nov 16, 2006
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I'm with @citay here.
Even more: a DDR4 module at 1.5V runs very hot.
That's not good for the long-term health of your system.
 
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