Zen 4 and DDR5 - performance, stability, POST times?

[chris.nz]

Hi all,
I'm looking to buy a 7950X system with 64GB RAM, and trying to figure out the best RAM configuration to go with. I'm aware of the benchmarks showing Zen 3 systems getting a small but noticable performance boost from using 4 sticks of RAM rather than 2. I've also seen various vague references to the same being true on Zen 4, but yet to see any real benchmarks or other clear evidence of this. Given it seems much harder to have 4 sticks running stable at high clock speeds, I'm wondering if in practice we're back to the "2 sticks are better than 4" rule of thumb with Zen 4? Does anyone know of any benchmarks or other detailed analysis of this topic they could point me at so I can understand this better?

Performance and stability of 2 vs 4 sticks aside, I've also seen the reports of very slow (20-60 seconds seems typical?) boot times with the current batch of AM5 motherboards. It seems like even with "Memory Context Restore" enabled (which disables memory training), the memory size, DDR5 speed, and number of sticks might still affect the boot time. Is this something that has been addressed in recent BIOS updates or is it still a problem? Are some motherboards worse offenders than others in this regard? Does anyone know of any recent articles or benchmarks that cover this in detail?

Many thanks for any help on clarifying the above!

 

[SpyderTracks]

Hi all,
I'm looking to buy a 7950X system with 64GB RAM, and trying to figure out the best RAM configuration to go with. I'm aware of the benchmarks showing Zen 3 systems getting a small but noticable performance boost from using 4 sticks of RAM rather than 2. I've also seen various vague references to the same being true on Zen 4, but yet to see any real benchmarks or other clear evidence of this. Given it seems much harder to have 4 sticks running stable at high clock speeds, I'm wondering if in practice we're back to the "2 sticks are better than 4" rule of thumb with Zen 4? Does anyone know of any benchmarks or other detailed analysis of this topic they could point me at so I can understand this better?

Performance and stability of 2 vs 4 sticks aside, I've also seen the reports of very slow (20-60 seconds seems typical?) boot times with the current batch of AM5 motherboards. It seems like even with "Memory Context Restore" enabled (which disables memory training), the memory size, DDR5 speed, and number of sticks might still affect the boot time. Is this something that has been addressed in recent BIOS updates or is it still a problem? Are some motherboards worse offenders than others in this regard? Does anyone know of any recent articles or benchmarks that cover this in detail?

Many thanks for any help on clarifying the above!

This is a very good question, and something I haven't researched a lot on. The person to look at on YouTube is Buildzoid on this channel

https://youtube.com/@ActuallyHardcoreOverclocking

Or Gamers Nexus

I'm not at my desk ATM but will have a proper search in a mo

 

[SpyderTracks]

Some worthwhile videos

 

[SpyderTracks]

Are some motherboards worse offenders than others in this regard?

From what I've heard, avoid Gigabyte boards this generation

 

[SpyderTracks]

Performance and stability of 2 vs 4 sticks aside, I've also seen the reports of very slow (20-60 seconds seems typical?) boot times with the current batch of AM5 motherboards. It seems like even with "Memory Context Restore" enabled (which disables memory training), the memory size, DDR5 speed, and number of sticks might still affect the boot time. Is this something that has been addressed in recent BIOS updates or is it still a problem?

I believe this was mostly on Gigabyte boards where it would do a RAM "retrain" on every boot no matter if memory training was selected or not, this is mainly resolved now, but personally, I'd still steer clear of Gigabyte boards due to various issues

A rather unique problem with DDR5 RAM...

Hi everyone, Really hoping someone can help me out. I have an incredibly unique problem, one that I can't find anyone else having (there are some, but with some major differences). I have been using 64gb of DDR5 for the past 2 weeks and everything worked fine (Aorus DDR5 6000MHz 16x4). However, I...

linustechtips.com

 

[chris.nz]

Thanks @SpyderTracks! As far as I can tell all those videos are talking about Intel CPUs/MBs, so I'm reluctant to read too much into them. I appreciate many aspects of DDR5 hold true regardless what platform they run on, but I'm trying to understand the AM5/Zen4 specific side of things. I've done some searching without much luck, seems like it's a topic ripe for someone to do a deep dive into.

Hmm what are the other issues you know of with the Gigabyte boards? [edit: I just saw your link on this. Not too sure I'd blame Gigabyte for that, running 4 sticks @6000 seems like pushing the limits on any MB?]. From what I've read most/all AM5 MBs seem to have fairly slow boot times, I've seen a bunch of complaints about boards from ASRock, ASUS, MSI, Gigabyte. I believe it was ASRock that had a particularly bad problem with it and put out a patch, but Memory Context Restore aside, it seems the boot can still be quite slow and it might need an AGESA update from AMD.

There's some interesting comments in this thread, including some talking about slow boot times, as well as success running 4 sticks at DDR5-6000:

https://www.reddit.com/r/Amd/comments/yw9g0a

I'm starting to think it might be best to hold off ordering a new system for another month or two until the dust settles a little, or at least to avoid 4 sticks even if it means giving up a little performance, I'd much rather have 100% stability.

 

[SpyderTracks]

Hmm what are the other issues you know of with the Gigabyte boards?

We've seen repetitive issues with gigabyte boards for 3 years or so now generally.

They double up on beep codes, so they'll mistakenly put say a CPU error beep code referencing a GPU error. All their documentation states it's a CPU error, but if you scour the web you'll find it's actually a GPU error

Hello new pc i connected the hdmi cable to my monitor no signal (i think i might need a reinstall of windows 11 were can i get a copy ?)

Hello new pc i connected the hdmi cable to my monitor no signal (i think i might need a reinstall of windows 11 were can i get a copy ?)

www.pcspecialist.co.uk

Plus in some instances, we're talking about 5 minutes to post for no discernable reasons.

That's on Intel or AMD platforms BTW

I think there's a lot of confusion with AMD boards with the new EXPO RAM settings. From what I understand DOCP (AMD's version of XMP) is separate from the new AM5 EXPO setting, and I think a lot of people have been setting them both and then getting unbootable systems.

But as I understand it, just use EXPO on a DDR5 system and ignore the old DOCP. EXPO essentially replaces DOCP and is far more tailored to the voltage requirements specific to DDR5.

So from what I've seen so far (which isn't a great deal I'll be honest) most of the DDR5 issues on AMD have been related to having DOCP and EXPO applied simultaneously.

 

[chris.nz]

We've seen repetitive issues with gigabyte boards for 3 years or so now generally.

They double up on beep codes, so they'll mistakenly put say a CPU error beep code referencing a GPU error. All their documentation states it's a CPU error, but if you scour the web you'll find it's actually a GPU error

That does sound painful! It puts me in a bit of a quadary though, as PC Specialist only currently offer ASUS and Gigabyte AM5 MBs and I had been leaning towards Gigabyte. I'm somewhat adverse to ASUS as I have an ASUS laptop and I haven't been impressed with Armoury Crate and their various other bloatware, though I hope I can avoid installing any of that on a desktop PC without losing out much in the way of functionality.

So from what I've seen so far (which isn't a great deal I'll be honest) most of the DDR5 issues on AMD have been related to having DOCP and EXPO applied simultaneously.

Interesting, and good to know. It seems to me that a lot of people are just using XMP sticks instead of EXPO and I wonder how much if anything that has to do with some of the problems people are seeing too.

 

[SpyderTracks]

That does sound painful! It puts me in a bit of a quadary though, as PC Specialist only currently offer ASUS and Gigabyte AM5 MBs and I had been leaning towards Gigabyte. I'm somewhat adverse to ASUS as I have an ASUS laptop and I haven't been impressed with Armoury Crate and their various other bloatware, though I hope I can avoid installing any of that on a desktop PC without losing out much in the way of functionality.

I hear you, and even though Asus themselves claim that Armory Crate can link to iCue, anyone that's actually tried it I think would agree this just aint true! But you don't need to install any of the Asus bloatware if you don't want to.

Our resident RGB expert @IRLRobinS has had a lot of success with an open source bit of software called OpenRGB which can support iCue and Asus Armory Crate RGB controllers as well as most others, it's well supported as well I believe so they are addressing updates where needed

Powerful Master Fan Control software

To be honest, I don't think it's any more effort than setting a fan curve in BIOS or other applications, and it certainly gives you a lot more options and control. Here's a walk through of my current fan profile for example: I've my rear exhaust fan connected to Chassis1 fan header, my top...

www.pcspecialist.co.uk

But I think from a general stability and troubleshooting standpoint, Asus Mobos are quite ahead.

 

[B4zookaw]

I’ve an Asus motherboard and very happy with it. The BIOS is good and general consensus across tech reviews and content I’ve researched is that Asus are very well regarded.

But as this video shows, across manufacturers RGB software is a horror show.

But OpenRGB is opensource and cross platform, so allows you to control RGB from different manufacturers with one app. And it’s only around 20Mb as opposed to Corsair iCUE’s 1 Gb+ install. Def worth a look, regardless of which MB you go with.

 

[chris.nz]

I actually want to make sure I can turn any and all LEDs off, I'd rather there weren't any at all but that seems quite hard to avoid these days! It's quite ironic given I work on some fairly complex LED projects at times, but this will primarily be a workstation that I want to be hidden away under a desk rather than shouting from the rooftops

Thanks both for voicing your votes of confidence in Asus, I'll definitely reconsider my view of their motherboards now.

 

[chris.nz]

For those who might be interested, I finally found a review that has benchmarks of different DDR5 memory speeds, as well as some benchmarks comparing 2 vs 4 DIMMs:

https://www.techspot.com/review/2534-amd-ryzen-7600x/#RAM_Performance

I found it via this discussion which is also worth a read:

https://linustechtips.com/topic/1457901-amd-7950x-128gb-ram/

As suspected, it looks like there is a gain when using 4 ram sticks, though a pretty small one and I'm not sure it's worth the possible stability issues it might bring.

 

[tikky]

About Gigabyte/Asus AM5 mobo's here's some interesting info/opinion here :

These are more budget orientated boards but I think he'll be releasing a vid soon covering a wider price range.