Long AM5 POST times

[ir_cow]

Ask the MB makers, it wasn't in the launch BIOS until people complained about 1min boot times lol. The struggles and dial up and waiting 10 minutes for windows to load was a real thing. Could go make. A sandwich and come back.

 

[Launcestonian]

Ask the MB makers, it wasn't in the launch BIOS until people complained about 1min boot times lol. The struggles and dial up and waiting 10 minutes for windows to load was a real thing. Could go make. A sandwich and come back.

Yes indeed, the memory training algorithms & when to stop doing it are still a pretty new thing with Zen 4.

 

[AusWolf]

The thing that bugs me about MCR is if its saved to a bios profile, then load another bios profile (with MCR on when it was saved) it still takes a couple minutes to boot with the chosen bios profile despite the fact that the bios profile is already saved (with the MSR on) . So shouldn't the motherboard be remembering the precise settings for the RAM from the bios profile in the first place & that of course includes MCR being on? I've seen this problem on an Asrock, MSI & even a Gigabyte AM5 boards I have here despite agesa updates for several months already. There is still work to be done to fix these bios problems with Zen 4.

MCR is a workaround. I wouldn't rely on it working perfectly 100% of the time. Also, why do you need multiple BIOS profiles? I just set up whatever works and leave it at that.

 

[Mussels]

The thing that bugs me about MCR is if its saved to a bios profile, then load another bios profile (with MCR on when it was saved) it still takes a couple minutes to boot with the chosen bios profile despite the fact that the bios profile is already saved (with the MSR on) . So shouldn't the motherboard be remembering the precise settings for the RAM from the bios profile in the first place & that of course includes MCR being on? I've seen this problem on an Asrock, MSI & even a Gigabyte AM5 boards I have here despite agesa updates for several months already. There is still work to be done to fix these bios problems with Zen 4.

Cold boots can't possibly risk that, because you never know if the RAM has been changed.

Ask the MB makers, it wasn't in the launch BIOS until people complained about 1min boot times lol. The struggles and dial up and waiting 10 minutes for windows to load was a real thing. Could go make. A sandwich and come back.

I'm just about to boot up my first AM5 system (not a clients, my own) and poke these things. I'll see what i can spot with boot times since i have a few kits of ram on hand today.
Been able to replicate the traditional slow boot problem with way too fast RAM for AM5, but that's half the point of trying to poke the bear

Stock settings works fine every time, but using EXPO with RAM guaranteed to push the board to it's limits was failing, often taking a few cycles to do before booting at JEDEC (4800?)
. Hearing the CPU fan spin up to 100,000RPM was a clear indicator of when the failed boots happend

DDR5 8000 on the Taichi Cararra
Running lower Infinity fabric speeds didn't help it booting - EXPO manually set 1.30vsoc and Fclk to 2000, as well.

Trying new BIOS now...

7600 works just fine, 8000 does the repeated failed boots.
I recorded videos, but had a dog running over my feet so it's more for me to use as a timer.


7600: 18 seconds
7800: same, 18ish seconds
8000: 120 seconds, BIOS booted at JEDEC

Lowering infinity fabric (FCLK) has zero benefit to the boot times, If the DRAM speed is too high it just fails. This will be due to whatever secondary and tertiary timings the boards are running and why BIOS updates make such a difference.



TL;DR: The CPU and board can both simply have limits you may be reaching, in MCLK or UCLK. BIOS updates may fix it, but rather than fight it just tune in the highest that boots reliably, including cold boots.

 

[OkieDan]

I don't see why a BIOS couldn't store serial numbers of RAM sticks along with timings in a profile. Simply boot with slowest JEDEC speeds, read profile, read serial number from RAM, then load better timings if serial numbers match and are in same slots and no new slots are populated. Seems like the only reason we don't have this is due to lack of commitment to make it happen, not because there's an insurmountable obstacle.

 

[Mussels]

I can confirm that changing RAM settings or swapping RAM does result in the next boot taking longer (about 30 seconds), but then the fast boots are back after that.
Repeated failures only happened with overclocking settings higher than my CPU could handle - in M F or U clocks, alone or combined.
The board had issues recovering from some of those, and those could be mistaken for very slow POST times.

I don't see why a BIOS couldn't store serial numbers of RAM sticks along with timings in a profile. Simply boot with slowest JEDEC speeds, read profile, read serial number from RAM, then load better timings if serial numbers match and are in same slots and no new slots are populated. Seems like the only reason we don't have this is due to lack of commitment to make it happen, not because there's an insurmountable obstacle.

That's ridiculously complex for no benefit to anyone. What do you think XMP and EXPO profiles are for, that's literally what they do - they store the timings for you.

The slow boots are not DRAM training, that's a 10 second job at worst.

 

[OkieDan]

I can confirm that changing RAM settings or swapping RAM does result in the next boot taking longer (about 30 seconds), but then the fast boots are back after that.
Repeated failures only happened with overclocking settings higher than my CPU could handle - in M F or U clocks, alone or combined.
The board had issues recovering from some of those, and those could be mistaken for very slow POST times.


That's ridiculously complex for no benefit to anyone. What do you think XMP and EXPO profiles are for, that's literally what they do - they store the timings for you.

The slow boots are not DRAM training, that's a 10 second job at worst.

When I have long boot times, DRAM LED is lit on motherboard for the vast majority of that time. What's it doing if it's not training?

 

[Waldorf]

@AusWolf
having multiple profiles, allows me to switch back to say jedec for ram,
but still has certain "optimizations" (e.g. on board audio off).

i prefer to not use XMP/AMP settings when doing fw/flash updates (or similar),
or just to have a fallback option if tweaking goes wrong, so i dont have to start from scratch,
or if tweaking gets interrupted, i can intermittently use the pc (stable) if i need to, just by loading a different profile.

@OkieDan
thats just showing where the POST is "at", not what is actually happening with the part.
i would guess related to voltages/clock/timing, tho i havent used any AM5 stuff yet.

 

[chrcoluk]

Feel like AMD need to make this work alongside fast posts, I never had this issue on any system I have owned ever.

Also question for owners of these boards, does it have to retrain when waking up from sleep, if yes to that, then that would drive me bonkers. Used to now days hitting the power button, and seeing my desktop within 2-3 seconds. Guessing no as sleep does keep the RAM in some kind of active state.

 

[Waldorf]

dont mind the sub 20s from powered down to desktop (no sleep modes etc on desktops for me),
but current AM5 "trouble" is why i wont swap yet.
at least not the first gen stuff, on a new socket.

 

[chrcoluk]

I just read a reddit post which states AMD5 only supports DDR4 speeds with 4 dimms, is that true? (3600mhz) . I mean their supported speed not what someone might get.

AMD can only guarantee the speeds below for DDR5 Ram


5200 mhz for 2 sticks


3600 mhz fo 4 sticks


If you set Expo and get ram to run faster then you have won the silicon lottery.

 

[ir_cow]

I just read a reddit post which states AMD5 only supports DDR4 speeds with 4 dimms, is that true? (3600mhz) . I mean their supported speed not what someone might get.

reddit fails again. AM5 doesn't support DDR4 at all lol.

 

[Belfaborac]

Depending on the actual RAM used, 4800 to 5600 is probably what you can expect with 4 sticks.

 

[Deleted member 223428]

reddit fails again. AM5 doesn't support DDR4 at all lol.

I'm pretty sure what @chrcoluk was referring to is the official RAM speeds supported by AMD. Meaning that DDR5-3600 (that doesn't even exist) is DDR4 like speeds.

From the 7950x3d specs page:

 

[chrcoluk]

reddit fails again. AM5 doesn't support DDR4 at all lol.

The guy said running DDR5 at 3600mhz to clarify. Thats why I said DDR4 speeds.

Someone posted that their 4 dimms were only stable at 3600mhz and below and asked if thats a problem, and the reply was AMD only officially support 3600mhz in a 4 dimm configuration. Have you done any 4 dimm DDR5 testing yet on either AMD or intel? it would be good if reviewers didnt only test 2 dimms.

I'm pretty sure what @chrcoluk was referring to is the official RAM speeds supported by AMD. Meaning that DDR5-3600 (that doesn't even exist) is DDR4 like speeds.

From the 7950x3d specs page:

View attachment 317769

Thank you, exactly the answer I was looking for, I feel the 4 dimm situation does need more exposure as thats a massive drop. Reminds me of barely been able to manage jedec speeds on my 2600X 4 dimms. But this seems worse given jedec for DDR5 is actually higher than 3600mhz.

 

[ir_cow]

I'm pretty sure what @chrcoluk was referring to is the official RAM speeds supported by AMD. Meaning that DDR5-3600 (that doesn't even exist) is DDR4 like speeds.

From the 7950x3d specs page:

View attachment 317769

ah... got it. Yep if you run 4x dual rank DIMMS it will boot at 3600 automatically. Tops out at 4800 if you have nice CPU and manually set it yourself. Probably have to play with voltages to get it to boot. I sure did.

4x single rank goes up to 6200 for me.

 

[R-T-B]

dont mind the sub 20s from powered down to desktop (no sleep modes etc on desktops for me),
but current AM5 "trouble" is why i wont swap yet.
at least not the first gen stuff, on a new socket.

If you mean the chips burning sockets that was resolved in firmware.

 

[Waldorf]

@R-T-B
no, talking about "everyday" users (with not so much experience building/setup),
getting brand new hw "the day it comes out".

lets say i didnt regret skipping 1st gen on AM4.
even my friend with a little experience (incl 2y in a local shop),
decided he will wait for next chip being out, before switching to AM5.

 

[Belfaborac]

To be honest, apart from the long boot times which are now a thing of the past, AM5 has been as problem-free as any computer I've ever built and significantly better than many.

If your intention isn't overclocking CPU and/or memory, but just getting a stable, really well-performing machine with a sane power draw up and running I'd say it's a no-brainier.

 

[Waldorf]

@Belfaborac
dont wanna make it sound like 7xxx isnt a good chip, just learned that most times,
its a good idea to skip the "1st one released", no matter what it is..

 

[ir_cow]

Remember Ryzen 1800X and all the issues. Give it another 2 generation and it will be perfect. Just in time for another socket and DDR6 lol

 

[AusWolf]

Remember Ryzen 1800X and all the issues. Give it another 2 generation and it will be perfect. Just in time for another socket and DDR6 lol

The last generation of a socket is always the best. Screw platform longevity.

 

[Belfaborac]

@Belfaborac
dont wanna make it sound like 7xxx isnt a good chip, just learned that most times,
its a good idea to skip the "1st one released", no matter what it is..

I quite agree; but was simply pointing out that in this particular case it hasn't held true, at least for me. If someone had asked me a while back, when boot and memory isses were still prevalent, I'd have said "naah, give it a while longer if you can". Now though, I have no qualms about saying "go right ahead".

Psersonally I can't wait to see what 8xxx will bring, although I have no need for more performance. Most likely I'll wait for 9xxx, since the rumor is that by then the inter-CCD latency will likely have been solved or minimised. If that turns out to be the case, then Intel really will struggle to keep up.

 

[AusWolf]

I quite agree; but was simply pointing out that in this particular case it hasn't held true, at least for me. If someone had asked me a while back, when boot and memory isses were still prevalent, I'd have said "naah, give it a while longer if you can". Now though, I have no qualms about saying "go right ahead".

I agree. All you need with AM5 is a BIOS update and you're good to go.

 

[R-T-B]

@R-T-B
no, talking about "everyday" users (with not so much experience building/setup),
getting brand new hw "the day it comes out".

lets say i didnt regret skipping 1st gen on AM4.
even my friend with a little experience (incl 2y in a local shop),
decided he will wait for next chip being out, before switching to AM5.

Yeah I was a 1st gen AM4 user too. I don't mind sorting through some of the issues for performance lol.