RAM won’t run at reported frequency

Posted by sirwaffleburger@reddit | buildapc | View on Reddit | 25 comments

I bought 6400 mhz DDR5 ram. I enabled XMP in the BIOS. I selected the 6400 mhz profile. The BIOS says its running 6400 mhz. I boot into computer and check the memory speed and it says 4800 mhz.

Ryzen 9 9900x, asrock x870 pro rs, DDR5 6400 mhz ram, rtx 2060 super, linux mint 22

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tybuzz@reddit

When you reboot into the bios again, what ram frequency is it reporting on the main page?

Try a bios update.

I am not familiar enough with linux to say if it's a linux issue though, hopefully someone else can say..

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grandmapilot@reddit

OS have no impact on how RAM CPU and MB interact on hardware layer

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tybuzz@reddit

Do you have any idea why it would not be running at the speed OP set, though?

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xderickxz@reddit

I'd just like to interject for a moment. What you're referring to as Linux, is in fact, GNU/Linux, or as I've recently taken to calling it, GNU plus Linux.

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AnomalyFriend@reddit

Are they in the correct slots? I had that happen but it turned out it was in the wrong slots

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sirwaffleburger@reddit (OP)

Theyre in slots 2 and 4 And i know those are the correct slots because it wouldn’t boot with them in 1 and 2

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Boltofdoom@reddit

This tells me you didn't read your manual

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kttm@reddit

I always thought amd used expo and intel uses xmp

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nas2k21@reddit

Is the ram on the qvl? My mobo says it can run 4133+ my kit is rated 3600, but it's not on qvl and unstable, bump it down to 3200, perfectly stable

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ecktt@reddit

AMD uses EXPO certified RAM. Even if the motherboard supports Intel's XMS, it's a different vetting standard. ie, there is no guaranty XMP only RAM will work.
There is no EXPO 6400MT/s RAM. Why? 6000MT/s is optimal. Anything higher requires manually OC the Infinity fabric (stability issues) or running the RAM in Gear 2(making everything slower than before)
EXPO (like XMP) is meant to make OC the memory controller (in the CPU) easier. There is no guaranty it will work. In fact, it voids the warranty. It would be up to AMD discretion whether they honor the warranty if something else goes wrong but they are not going to help you run the RAM faster.

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porn_inspector_nr_69@reddit

What ram can support is not the same than what your CPU and motherboard can.

Your best bet is to set the XMP profile and select freq down to 6000 or a notch below.

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skyfishgoo@reddit

how are you checking?

sudo dmidecode -t memory

is what i would recommend

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facukpoboca@reddit

I have the exact same issue on AM4. My RAM is rated for 3200mhz but I couldn't get it to run at its advertised speed when enabling XMP, it would set itself at 2600mhz automatically.

I couldn't really fix it, I had to manually set the speed to 3000mhz and disable XMP, which I guess is good enough, but if I go any higher it will default back to 2600mhz.

Hope this helps.

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sgtnoodle@reddit

We're you adjusting fclk appropriately?

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Available-Quarter381@reddit

Your board is resetting it when saving because it's not supported/stable

You have ryzen, run 6000 cl30 if it doesn't work loosen the timings until it does

Above 6000 is more or less pointless on AMD processors

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