13900K + Z690 RAM Speed slower than Z790?

Fatpizza

Fatpizza

Fatpizza

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With Raptor Lake I was under the impression that it was the memory controller on the CPU that dictated the RAM compatibility rather than motherboard?
For example I used to have my 13900K running an 8000Mhz GSkill 48GB kit in an ASUS Z790 Apex with absolutely no problems. But when putting the same RAM and the same CPU into a AsRock Z690 Aqua OC, I can't run it stable past 7000Mhz no matter what I do. I'm not really that fussed as the performance difference in reality is minimal, but it's still slightly annoying. Especially since the Aqua OC is supposed to be such a high end board.
 
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The motherboard as somthing to do with memory speed. Its literally on there site.
Anything passed the Intel memory supported speed 5600 is an OC and down to a lot of factors, the main one been the motherboard.


AsRock Z690 Aqua OC
  • Supports DDR5 non-ECC, un-buffered memory up to 7000+(OC)*

ASUS Z790 Apex
  • Supports DDR5 non-ECC, un-buffered memory up to 8000+
Intel ARK
  • Memory Types Up to DDR5 5600 MT/s
 
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Wing-Man said:
The motherboard as somthing to do with memory speed. Its literally on there site.
Anything passed the Intel memory supported speed 5600 is an OC and down to a lot of factors, the main one been the motherboard.


AsRock Z690 Aqua OC
  • Supports DDR5 non-ECC, un-buffered memory up to 7000+(OC)*

ASUS Z790 Apex
  • Supports DDR5 non-ECC, un-buffered memory up to 8000+
Intel ARK
  • Memory Types Up to DDR5 5600 MT/s
Click to expand...
Thanks. I had seen that, but I'd figured that may have been a holdover from when it was the first released with Alder Lake CPUs. And there are many reports that improved memory controller of Raptor Lake allows higher RAM speeds. But that is obviously still somewhat limted by the motherboard.
Plus I'd seen all these reports of overclockers getting DDR5 to run at 7960Mhz, but when looking closer that was with a single DIMM at absolutely horrible timings.
 
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Fatpizza said:
Thanks. I had seen that, but I'd figured that may have been a holdover from when it was the first released with Alder Lake CPUs. And there are many reports that improved memory controller of Raptor Lake allows higher RAM speeds. But that is obviously still somewhat limted by the motherboard.
Plus I'd seen all these reports of overclockers getting DDR5 to run at 7960Mhz, but when looking closer that was with a single DIMM at absolutely horrible timings.
Click to expand...

If you spend time reading BIOS change notes they sometimes go into a little detail about improving RAM compatibility or support for greater (OC) RAM speeds etc. So I have typically figured that the CPU is only one part of what is needed to ensure compatibility and faster RAM speeds with tighter timings.
 
can you run TestMem(tm5) anta777 and show a screen shot


your board as had bios updates to support faster ram, but the board/cpu you have is not the same as his so..
if he plays about he could get faster speeds but with loose timings
 
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When my RAM was set to 7200 I was able to run Cinebench with no issues for over half an hour, but as soon as I ran memtest86 errors started spewing out.
6933 ran memtest86 successfully once but had one error on the 4th pass on the 2nd attempt. 6800 was perfectly stable over multiple attempts.

That's with setting XMP and then just changing the frequency. Didn't touch the timings.

I'm OK with 6800. My main concern was that I'd done something wrong and would have to pull my PC apart to re-seat the CPU. :P
 
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Fatpizza said:
With Raptor Lake I was under the impression that it was the memory controller on the CPU that dictated the RAM compatibility rather than motherboard?
For example I used to have my 13900K running an 8000Mhz GSkill 48GB kit in an ASUS Z790 Apex with absolutely no problems. But when putting the same RAM and the same CPU into a AsRock Z690 Aqua OC, I can't run it stable past 7000Mhz no matter what I do. I'm not really that fussed as the performance difference in reality is minimal, but it's still slightly annoying. Especially since the Aqua OC is supposed to be such a high end board.
Click to expand...
Second gen motherboards are often better at overclocking due to a maturing platform in which a lot of bugs are ironed out.

Motherboards have a strong input into memory compatibility so I'm not surprised that Z790 is much better than Z690, just have a look at the memory QVL list.
 
Autode1ta said:
yes it is. I usually just run memtest from the bios.
Click to expand...
Rather flash memtest to a USB drive and run it off that.

You can then put the RAM under serious stress using very intense settings.

I also agree that TestMem(tm5) using the anta777 extreme config is also ideal. Buildzoid and other overclockers use a few tools to make sure that RAM is stable as different tools push RAM differently (single core v multi core can affect RAM usage very differently).
 
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I've also found Z690 a bit fussy with memory speeds compared to Z790, as an example using an EVGA Z690 Dark (which was probably the best Z690 board for memory OC'ing) it topped out around 7200/7400 on 16GB A Die sticks. However, it was possible to bench 8000+ on it but it wasn't fully stable, I do know of a few examples on Z690 Dark's which are running 8000 stable. Z790 is a lot easier to hit higher speeds, I have both a Z790 Dark and Apex here at the moment and both can hit over 8200 with ease. I have had the Apex up to 8800 but that isn't fully stable and needs a bit more work

In short, Z790 is easier to get higher memory speeds on as a rule of thumb.

Also oddly the 24GB M-Die sticks seem a bit easier to drive but I have not tested those on the Z690, as I have sold my Z690 Dark now.
 
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Wing-Man said:
The problem with memtest is you need to run it for a day.

Testmem I feel is a good fast test it tends to find errors in no time
Click to expand...

Hi, I found this post via a forum test as I'm having problems with screen freezes and want to rule out RAM as I've recently replaced it.

Could you post a link to Testmem please, my Google-Fu is bringing up Memtest.

Thanks
 
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