BSOD with new 64gb RAM....what am I doing wrong?

Z-U

Z-U

Associate
Joined
6 Oct 2020
Posts
31
Hi all, I wonder if someone can advise me on something...I'm a novice compared to you guys.

I have 64gb of Corsair Vengeance LPX....apparently sold as AMD Ryzen-ready or whatever the term was...

These dimms are CMK64GX4M2Z4000C18 (ver 3.44 if that's important).

Whenever I put them in the computer I've been going to the Bios and putting them to XMP 2000mhz....thats not 1:1 coupled mode with Fabric Clock, but I assumed it would still work. ANd it does - for a bit.

However, if I try to play a game or anything else more taxing like Unreal Engine - it BSOD's and needs a reboot and Bios reset

My questions is do you have to manually set the voltages for the memory to 1.35v if you're using XMP mode? I'd always assumes that putting it into XMP mode would change the voltages to the right settings....but maybe thats not the case? I've never had ram this fast - nor 64gb of oit. And having just checked the memory compatibility list on the Gigabyte website....these dimms are not actually listed yet...but I'm just hoping I've not wasted company money.

Spec:
Ryzen 9 5950 (PBO up to 4.5ghz only, I think the fabric clock is just running standard at 1800 - I've not tried higher and don't know how to)
Gigabyte X570 Aorus Master
Gigabyte 3090RTX Eagle OC (not overclocked)
MP600 C: drive
BeQuiet CPU AIO water cooler.
BeQuiet 601
BeQuiet 1000w PSU

Any advice on what I can do to stabilse this memory would be greatly appriecated. I can see it works...I just can't make it stable for strenuous tasks.

Thanks
 
Man of Honour
Joined
22 Jun 2006
Posts
11,675
It's always a good idea to check if the voltages were set, yes. Though, I doubt if it would even boot at 4000 Mhz if it was still using 1.2v.

I'd also suggest manually setting the memory to 3600 at 1.355v, then running some tests to check stability and go from there. 4000 Mhz is right at the edge of DDR4 so it's expected that it might not just be plug and play.
 
Associate
Joined
11 Dec 2016
Posts
2,023
Location
Oxford
XMP does set voltage. Might still not be enough.
Try to increase voltage manually, 1.4V should be safe. Just to make sure this is unstable clocks/timings issue.
Less likely that some memory controller voltages need to be adjusted. 64GB will put a lot of load on memory controller

Meanwhile I would run this in 1:1 mode, at 1800/3600 (or 1900/3800 if it works) with XMP enabled anyway. Might kill two birds with this - make it stable as clocks are lower, and gain some performance from 1:1 mode.
 

Z-U

Z-U

Associate
OP
Joined
6 Oct 2020
Posts
31
I'll check that voltage...but setting it to 3600 - how do I do that? I can only see the default setting or XMP in the normal XMP option - not multiple profiles....I've never delved into the manual tuning of memory before.
 

Z-U

Z-U

Associate
OP
Joined
6 Oct 2020
Posts
31
Thanks for the responses....I think it's the manual tuning of the ram I don't understand....at all. Are there other profiles that are considered stable, but they just don't show up in the Bios?
 
Soldato
Joined
15 Oct 2019
Posts
11,701
Location
Uk
Will struggle to run ram at 4000mhz on ryzen especially 64gb. If you download the ryzen dram calculator then you can set what speed you want "recomend starting at 3600mhz" and it will spit out a bunch of timings and voltage that you can input in the bios.
 
Man of Honour
Joined
22 Jun 2006
Posts
11,675
I'll check that voltage...but setting it to 3600 - how do I do that? I can only see the default setting or XMP in the normal XMP option - not multiple profiles....I've never delved into the manual tuning of memory before.
Usually it's just DRAM frequency or something like that, it will automatically set timings, but you'd have to manually set the dram voltage.
 
Associate
Joined
2 Nov 2012
Posts
900
Location
Sussex
@Z-U Guessing the BIOS for your board is the same as mine. Set the XMP profile and then set the System Memory Multiplier to 36.00 (just type in 36 and hit enter). This will show in the left column, the XMP value of 40.00 will show in the right. Save and exit and see if it boots. If it doesn't drop the multiplier down to 32.00 and then try working back up to see what your CPU can handle. Anything above 3200 is officially an overclock on 5000 series CPU's.
 

Z-U

Z-U

Associate
OP
Joined
6 Oct 2020
Posts
31
Yeah I'm on F33 at the moment - but I see F34 is available. I'm guessing that won't make much difference. I'll try what you've suggested and check it's getting 1.35v too. Cheers guys - very helpful. I'm not sure this was what I intended. I have 32gb of TeamGroup 3600MHZ anyway....feels like overkill. :) (Which i always enjoy)
 

Z-U

Z-U

Associate
OP
Joined
6 Oct 2020
Posts
31
Grrrr this is so frustrating...

So first run - set XMP, but noticed the voltages are just set to Auto, so I changed it manually to 1.35v....no joy - just cycles the POST cycle two or three times and reset the bios back to normal - however it also said in the Memry Profile that XMP mode was active...but in CPUZ it's reporting JEDEC#16 numbers and 1333mhz uncore frequency.

So I then went and set the multiplier to 36 as per @stephenb's post....it didn't cycle the post sequence over and over - it booted first time successfully, but then in CPU-Z it's still just reporting 1333mhz JEDEC#16 numbers again...what am I doing wrong?

In CPUZ SPD Tab shows 4 timing tables.

JEDEC#16 : 1333mhz CL22-18-18-43-61 1.2v
JEDEC#17 : 1333mhz CL23-18-18-43-61 1.2v
JEDEC#18 : 1333mhz CL24-81-18-43-61 1.2v
XMP-4000 : 2000mhz CL18-22-22-42 64 1.35v

Even if I could get this running at 3600mhz - the capacity is what I bought them for. Anyone any further advice?

Thanks for all your help folks.

"Optimized For Ryzen"

https://www.corsair.com/uk/en/Categories/Products/Memory/VENGEANCE-LPX/p/CMK64GX4M2Z4000C18

....so whats happening here? Is it fundamentally that Zen 3 can't support with 4000mhz? Or Is it that the BIOS is not upto date? F34 is available, but release notes just say that it's just to support Cezanne APU's.
 

Z-U

Z-U

Associate
OP
Joined
6 Oct 2020
Posts
31
Sorry to keep answering my own thread.....got this up and running now - at 1.36v....what else can I do to improve the timings?

https://ibb.co/BBrR68L
BBrR68L
 
Last edited:
Associate
Joined
2 Nov 2012
Posts
900
Location
Sussex
I'm confused. You said you had 64GB but your CPU Z screenshot shows 128GB :confused: Did you buy two sets of the 64GB kit?

Either way your timings are horrible and miles off the XMP profile. I'd be tempted to load optimised defaults in the BIOS and then start over from scratch.
 
Associate
Joined
11 Dec 2016
Posts
2,023
Location
Oxford
Sorry to keep answering my own thread.....got this up and running now - at 1.36v....what else can I do to improve the timings?
BBrR68L
To get there quickly, make it use XMP timings at 3600MHz. Safe bet they will work, it was already almost working at 4000.
So try and activate XMP again, but set multiplier tp 36 and voltage manually like you did already

If that doesn't work, manually set main timings to what is shown in CpuZ SPD for XMP-2000 mode, leaving rest to Auto.
 
Back
Top Bottom