X870E/9800X3D: EXPO 1 fails, XMP 1 works

OverDrive

OverDrive

OverDrive

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I have just got up and running with the Aorus Master X870E and a 9800X3D. I am using 2x 32 GB Corsair Vengeance 6000/C30 (XMP and EXPO compatible) The board is running the latest BIOS.

EXPO 1 fails to boot.
XMP 1 boots ok.

It’s not an issue as I always used XMP before, just wondering why EXPO 1 failed though?

Any thoughts? Thank you.
 
EXPO probably uses more aggressive timing and the CPU can't handle it. The XMP profile is likely a little looser and easier to run.

Remember, XMP and Expo are actually auto overclocking so there's no promise that they will work - you could try manually tweaking the settings but I'd just leave the RAM on XMP and be happy.

Reply with the exact timings of each.
 
Thanks for the reply. Yes, I was reading about EXPO being more aggressive.

The default timings for both EXPO and XMP in the BIOS are: 30-36-36-76.

The boot failure message when trying EXPO says the memory speed is 4790.92Mhz. Is this to be expected?
 
OverDrive said:
Thanks for the reply. Yes, I was reading about EXPO being more aggressive.

The default timings for both EXPO and XMP in the BIOS are: 30-36-36-76.

The boot failure message when trying EXPO says the memory speed is 4790.92Mhz. Is this to be expected?
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That’s weird. No, your RAM is not going to run at 4.8 gigahertz. Thats impossible.

Maybe a bug in the BIOS but I’m not sure. It could also just be the JDEC speed of 4800 MT/s being reported as Ghz which is incorrect.

RAM speeds are measured as double the frequency since its double data rate - 6000 MT/s is 3000 mhz since the RAM is polled twice per clock cycle.

On the XMP/EXPO, I wonder if the sub timings of the XMP and EXPO profiles are different then?

I might search for Reddit posts with your motherboard and BIOS mentioned to see if the version of the BIOS you are currently running is a bit buggy and potentially move to an older more stable version.

That being said, RAM is difficult to investigate/OC in person, let alone via a forum post so I might not be as much help as I think you’d need but I can infer from your replies and give you a general idea of what to do.

I’ll have a quick look myself and see what I can find but I probably wouldn’t stress about it too much for now.

Can you upload print screens of your CPU-z, BIOS version and BIOS timings please?
 
Thank you so much for your help. I am not at home at the moment. I took these photos last night though.

The fourth photo is just a dialog to enable the X3D turbo mode, however behind the dialog box you can see the RAM speed being reported as 4815.26Mhz. However on the third photo of the BIOS main page the RAM speed appears to be reported correctly.

IMG-3869.jpg

IMG-3870.jpg

IMG-3871.jpg

IMG-3874.jpg
 
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Ok so the first image is just incorrectly reporting MT/s as hz.

Going to suggest manually setting some voltages but I’m not fully up to speed on AM5 voltage settings.

Manually setting voltages like SOC and DRAM can have a big improvement on system stability when overclocking, especially with RAM capacities of more than 32gigs.
 
Thank you :) How come it’s 4790 MT/s on the fail message? Is this correct? How come the main page says 6016 MT/s? I’m slightly confused.

Would be happy to manually set some voltages that you suggest.

Should the MT/s not be double the MHz, so around 6000MT/s for 3000Mhz memory?
 
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OverDrive said:
Thank you :) How come it’s 4790 MT/s on the fail message? Is this correct? How come the main page says 6016 MT/s? I’m slightly confused.

Would be happy to manually set some voltages that you suggest.

Should the MT/s not be double the MHz, so around 6000MT/s for 3000Mhz memory?
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Because it’s loaded the JDEC base speed for that RAM as a safe setting to get the system to POST when it fails to run the OC settings.

Like safe mode.

Main page says 6016 MT/s because it’s your BCLK (100.26 mhz) frequency times your memory frequency (3000 mhz or whatever) times 2.

Your RAM voltage is round about 1v which might be too low.
 
Found this thread on Reddit and it looks like you're not the only one having issues.

My thoughts are that it's an AGESA issue where AMD and AGESA don't always play nicely together for the first while but the issues will be resolved in the long run and you should just run the XMP profile for now and keep an eye open for BIOS updates in the future.

AMD usually has buggy software out of the box but in the long term, it's fixed and often results in performance gains - it's a pity that they do this with such an expensive motherboard but hey.

I'll try post some safe voltages for you to try when I have a moment.
 
I found this guide and read it but I woudn't do any BCLK overclocking as that is quite advanced and can be sort of risky (any sort of OCing is risky but playing with the chipset frequency is getting up there where it can result in data loss, stability and damage to components if you get it wrong)

Read this too

It's a bit of effort but applying undervolting can give you a really nice little booste to performance for quite a small amount of effort - I did it to my AMD 5700X and it worked a treat.
 
Thank you for the replies and links, and for looking into this for me. I will have a good read and reply back. It may be a couple of days though as I am not back home until Weds. I really appreciate your time and insight.
 
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