Infinity Fabric Puns

TL:DR - I re-synched my IF at the 1:2 ratio which is the only other option my motherboard shows for Infinity Fabric to Memory Clock synchronization, the other option of course being 1:1. This allowed me to increase my RAM speed beyond the 3800 MT/s at 1:1 IF I'd been running for a few months now to see if I could get the RAM speed to be higher enough to overcome the latency penalties inherent in doing so, and then to see how different programs respond to that tradeoff. The former is now complete, the latter is ongoing.

Discussion: The conventional wisdom in AMD land is that for best performance the Infinity Fabric must always be 1:1 synched with the memory clock. "Everyone knows this!" We see this being said all the time, even used as a club in certain discussions in lieu of presenting actual data. After watching a Buildzoid video on Youtube a while back where he discussed this, and pointed out that if you can set your memory speed higher enough with de-synched (or rather synched at a worse ratio) IF it could still be an advantage to do so despite the higher latency.

I finally got around to trying this out. After ensuring I had my current bios profile safely stored off on a USB stick, I reset all my secondaries and tertiaries to Auto, reset my primaries to very sloppy settings up in the low 20s, and then started jacking up the memory clock. I booted successfully at 4266MT/s but failed to boot at 4400MT/s so I stopped at 4266. I didn't try any shenanigans to see if I could goose the machine into booting at 4400MT/s or higher with some more twiddling, so it's possible that through some further playing around those higher speeds could be achieved.

I then spent the next 4-5 hours dialing my primaries, secondaries, and tertiaries back down.

I stopped at 16-16-16-28 for the primaries. For completeness I should have attempted CL14, and may go back and do that. CL16 worked, and I just assumed that CL14 (same as I achieved at 3800) would be a bridge too far, so I didn't pursue it. I probably should.

Result: Here's my Zen timings for my 3800/14-15-15-28 profile that I had. Btw, I had intended to set those 15s to 14 and retest back when I was OCing my RAM and just never got back to doing it, and since the benefits to doing so I knew would be exceedingly modest, I just never got around to it.

Here's a representative AIDA64 memory/cache

Pretty much just the title.. my computer recently started having reboots that remind me of when I was trying to tune for 1900 FCLK. Currently running 1867 FCLK and my previous test that I thought was instigating an unstable infinity fabric is not failing, so either I have another issue or that was never a test that covered my IF.

Thanks in advanced!

Hello guys! I have a 5900X, B550 MSI Tomahawk and Crucial Ballistix 3600mhz CL16 2x8gb (single rank, Micron E-die).

So my problem is.. I had that spec from above running on 1900mhz Infinity Fabric and 3800mhz@CL16 on 1.4v for a few months (I think even 2000IF was possible but I'm losing performance because of CL17). Today I got some dual rank Kingston Fury 2x16GB 3600mhz@CL16 on discount and tried to test them. They are Hynix DJR. On start I was getting surprising result, they were able to do 3800mhz@CL15 on around 1,45v but then I realised in ZenTimings then IF has a desync and runs on low freq so i fixed it and...suddenly it turned out I couldn't get a stable 1900 IF this time. Could it be possible that dual rank puts some more load and I'm unable to get higher IF now? Or my RAM could go faulty because of too high voltage out of sudden? It still boots on XMP in theory and doesn't drop errors then. Any confirmed info and what could I test/check?

Hey I've recently upgraded my PC to the following:

• Ryzen 5900X
• NZXT B550 N7 (latest P1.50 BIOS)
• 2x16GB Kingston Renegate 3600 CL16
• Be quiet Dark Power 12 750W

With 3600mem/1800 IF it's failing Prime95 Large FFT test (hardware error shortly after starting workers).

Small FFT tests are fine so I suspect it's related to IF/memory. The system is stable when I drop memory and IF to 3400/1700.

Funny enough, my PC boots even with 4000/2000 settings but running Large FFT is causing total system freeze.

Things I've tried:

• replaced memory modules with another pair
• undervolting/bumping voltages as suggested in guide1 guide2 guide3

Am I just unlucky and 1800IF is not guaranteed?

EDIT: Zentimings/HWINFO screenshot: https://i.imgur.com/bBxtyW0.png

EDIT2: SUCCESS!

For reference, this is the machine I have:
Ryzen 9 5900HS CE with 4266 Mhz LPDDR4x. And it runs the Infinity Fabric (FCLK) at a measly 1600Mhz, while it should be 2133Mhz.

There's absolutely no reason it shouldn't be possible to change it, either through a lightweight Ryzen Master app for mobile APU's, or start pressuring OEM's to include it in their BIOS.

There is AATU (AMD APU Tuning Utility), but this does not allow changing FCLK, only control the dynamic FCLK scaling.

This is not just a problem on the specific laptop I have, this is a widespread issue that needs addressing. It's literally performance we are missing out on...

EDIT: Should be possible for ALL Ryzen APU's.

Looking in HWiNFO64 I see that my memory is running at 1600MHz, but my IF is only at 1500MHz. What would be the correct way to fix this? I am just using an XMP profile. My motherboard is the X570 Taichi.

Just wondering, thanks!

EDIT: For those wondering why not 3600 / 1800, I'm running a 5800x on an X470 mobo that still has a limited set of supported RAM speeds. Potentially something that will be fixed with a BIOS update but was just wondering what would be optimal until then.

So I recently built a new PC with a 5900X and 32GB 4000Mhz RAM and a B550 Aorus elite V2 with a 360 AIO

I am new to overclocking but the CPU overclocking with PBO was going good so I decided to try and rund FCLK 1:1 with RAM. I set it to couple in Ryzen Master and it prompted me to restart my PC. After that the PC and the lights turn ON but there is no display output.

I have tried resetting CMOS which was successful since now the LEDs all turn on with even with PC turned off.

How do I reset the FCLK back?

I was having the hardest time getting to 2000 mhz IF even with every tweak. Ended up running 1900 and my ram at 3800 mhz with tighter timings. Even then I would have small periodic stability issues. Just updated to bios 33F on AORUS Master x570 and boom! 2000mhz IF and 4k Ram is now stable. Been running for a few days now no instability issues.

UPDATE - One user advised I should run OCCT to check stability. I downloaded and ran it and a couple of WHEA errors show up after running SSE for 30 mins. Not sure what that means. I download BIOS 33h and did XMP, IF to 2k, FCLK==MCLK, and resizeable bar to enable and it booted right up. Re-ran OCCT still same WHEA errors noted but I haven't noticed anything using my PC. Any advice on how to remedy those errors. Using stock XMP setting.

UPDATE#2 - Lowered to 1967 and 3933mkhz and the WHEA errors are gone on OCCT. OK, more tweaking will have to be done to try and get the 2k to long-term stable. Thanks for the input. I guess I got past the huge hurdle of getting 2k to post and run. I'll keep working on it and let everyone know. Thanks all for the feedback. Appreciate the more experienced users giving me a heads up!!!

Title. can anyone eli5 infinity fabric for me? Is it exclusive to AMD GPUs? If I pair a nvidia card with an AMD cpu, infinity fabric won’t work? is it just another name for something else? I consider myself pretty technically experienced and even the wikipedia article I was like ???

Hi everyone,

I got a TR 3990x running currently on a Gygabyte Aorus Extreme TRX40 mobo (crap board btw) and coupled with 8 x Gskill Neo 3800 sticks CL14 (timings are actually 14-16-16-36). By default on XMP memory profiles, the system would boot with FCLK at 1800 but memory is at 1900. So I would like to run on 1:1 parity and I was interested if anyone has succesfully ran stable a 3000 series TR with FCLK @ 1900 (mine doesn't post or if it does it quickly becomes unstable).

The whole system, except ram, is under water and I run a 4 GPU system.

So I'm forced to either to downclock the RAM to like 3600 and maybe attempt to tigthen the timings or go agove that like 3666 or 3733 and push the fabric a tad over 1800 for 1:1 parity. My problem is my mobo is crap and won't default BIOS post with 4 GPUs, giving a POST error d4 which can ONLY be bypassed if I get into bios and disable CSM support and enable Above 4G decoding (both are inversely defaulted). So if system becomes unstable, won't post or fails to train the memory timings, I have to disconnect 2 of the GPUs of the 4, without braking the loop apart, get rid of d4 error and then try the bios settings.

So yeah, anyway, I was curious if anyone got 1900 fabric running stable or that's some kind of unicorn for TRs! I'm trying to see if I got a shitty binned CPU or that's the norm.

Cheers!

So I have a Vega II Duo, curious if the fabric infinity link with work with a new W6800X Duo?

I called Apple, they were of no help. Emailed AMD, waiting to hear......

So to my knowledge, when setting ram speed on AMD systems you also want (need?) to set the infinity fabric to a specific frequency, and are looking for the ram speed to be divisible by the infinity fabric frequency. For example, 3600 MHz ram would have 1800 MHz infinity fabric. This makes sense to me so far. What I don’t get is why that is called 1:1. Now I’m not that great at math, but I would swear that ratio should be 2:1, or 1:2 depending on which is measured first. What am I missing?

Update 1: USB / Bluetooth dropouts / sound crackeling are sensitive to voltages, and can be fixed easily. I have to test if they are "more gone" at higher voltages, but I have been having no problems with default settings for low C-States, Global Power Management, SOC/Uncore OC Mode andprecision boost overdrive at vsoc = 1,060, vddg = 0,9, vddp = 0,85.

The only thing that remains are the Whea 19 Warnings and with my voltage testing (from vsoc = 1,040 - 1,166, vddg = 0,850 - 1,050, vddp = 800 - 1000) I can observe no difference with increasing voltages.

________________________________________________________________________________________________________

Do you have those issues too? Did you manage to fix them? Is it normal for the these problems to be irresponsive to voltage increases (in my example ~0,1v)?

Thanks for your help.

List of issues: (More detailed description below)

- Whea 19 warnings

- USB / bluetooth dropouts

My lowest voltage stable settings (multiple hours of prime95 and memtest).

Bios settings: Low C-States: off. SoC/Uncore OC Mode: on, global power management: off and precision boost overdrive: off

Whea 19 Warnings:

Even if I increase the vsoc voltage from 1.040 to 1.150 and vddg from 0.850 to 1.050 I can not get the Whea 19 warnings to disappear. I even get the warnings on 1900MHz fclk.

Lots of people have those issues with stable settings (maybe can be fixed with AGESA update).

USB / bluetooth dropouts:

I assume that the link between the soc and chipset was dropping out or getting asynchronous. (I was using the usb 2.0 ports of the chipset and the wifi / bluetooth module is connected to the chipset).

I thought these issues were fixed. Maybe they are not there with the higher voltages (I can test again).

I can't seem to be able to go over 1866 FCLK, can post at 1933 but not 1900 FCLK. Also have instability at 1933Mhz with WHEA errors while gaming. 3800Mhz cl14 ram kit

I am curious what everyone's experience has been. Anything above 1800 megahertz I am getting continuous whea errors constantly. As soon as it's dropped to 1800, the errors go away. I set the soc to 1.15 and all all other voltages for the motherboard are set to auto. I have Team Force xm 4000 sticks 2 x 16 with hynix cjr memory. I have a 5900 X. Ram voltage is 1.446 otherwise it's not stable at 3600 mhz. I can get the Ram to run higher without memory errors but as soon as Infinity fabric is above 1800, I have constant whea errors.

What's everyone else's experience been?

Running tests now to find the timing sweet spot for my ram

Hi Reddit!

I'm trying to push my FCLK optimally to 1900MHz to fit my upcoming G.Skill 3800C14 RAM kit. I'm pretty familiar with OC on Intel but total noob when it comes to AMD Ryzen.

My config:

Ryzen 5900X

Aorus B550 Elite Bios F13g (AGESA 1.2.0.1A)

32GB G.Skill 3600C19 soon to be replaced by 3800C14

I'm doing all my tests on RAM set to XMP which in normal circumstances is rock solid. VSoC is set to 1.1V which is enough for 1800FCLK. Rest is set to stock.

Story so far:

FCLK 1866 - just boots, runs, no fiddling required

1900 - doesn't boot at all, I need to clear CMOS by jumper

1933 - boots, WHEA errors in OCCT

1966 - boots, way less WHEA errors in OCCT (???), still not stable

2000 - hard lock, clear CMOS by jumper needed

I've tried setting VddG to 900-950mV but I see no difference. Same with setting VSoC to auto which results in 1.2V.

Since I don't know enough about AMD OC maybe someone could tell which voltages to tweak in attempt to make 1933/1966 stable. Also is this normal that 1900 straight out refuses to boot while higher frequencies at least get me to Windows?

I have the following system:

Ryzen 5 3600

Asrock B450M Pro4-F

2x16GB DDR4 PC3200 G.Skill Aegis

Radeon 5700 XT

UEFI version 2.7

XMP profile is active. I noticed in CPU-Z that the Northbridge (NB) frequency was exactly half of what the memory clock (MCLK) was. The MCLK is 1599.6 MHz (which seems correct for 3200 DDR RAM), but the NB frequency was only 799.8 MHz, which did not make sense to me, because my understanding is that MCLK should be equal to the NB frequency/FCLK.

In UEFI, the FCLK was set to AUTO. As a try, I then manually set the FCLK in UEFI to 1600 Mhz. Now FCLK and MCLK are displayed as identical in CPU-Z (1599.6 MHz both). The system seems stable and I ran a few benchmarks to compare. While not dramatically, the manual FCLK setting notably improves RAM and overall performance.

I am wondering now, if there could be any downsides/risks in having this manual FCLK setting. Is there any risk that this could damage components?

.

Infinity Fabric over 3600 = Lower cpu performance?! Eh? Ryzen 9 5950x

Greetings everyone.
I've recently installed a Ryzen 9 5950x on a b550 chipset motherboard and I'm struggling to understand what's going on. The more I explore, the more questions I have.

So, on many reviews I've seen online I see this cpu scoring above 10k Cinebench R20 in supposedly stock settings (no pbo), and clocking as high as 4.1Ghz on all-core load.
Other tests show scores on the high side of 9k with clocks between 3.8-4.0.

Here's what I'm mostly getting:
9450pts with clocks hovering around 4.6-4.7 peaking out at 4.8.
The cpu is not going above 74ºC, so I wonder how much impact temp is having here.

However, yesterday in desperation after trying everything I could think of, I turned my fclk from 2000 to 1600 to reflect what I see on most tests, and to my surprise the cpu clock speed went up! 3.8-3.9 and my score went from 94xx to 9726pts.
What the hell?
Higher infinity fabric clock leads to lower clock speeds? Eh? Is this a known factor?
What am I missing here?

Also more info

I was using a Gigabyte b550i Aorus Pro AX, with a 3950x and the best score I got (with pbo) was 9424pts (at least the highest I have the info recorded).
Then I got a 5800x, and on the Gigabyte it was flying! I can't remember the multi-core score or clock-speeds, but it was running above 5Ghz and scored a max of 652pts in single core cinebench r20.
Then due to some alterations on my system I got an Asrock b550 phantom gaming-itx and could never get the 5800x to run as fast.
I have limited thermal dissipation capacity on my tiny system, keeping the 5800x from throttling under heavy loads was a problem so I bit the bullet and got a 5950x.
It ran horribly on the Asrock!
In stock form it scored 9200-9400pts in cinebench. With PBO, it wouldn't go past 4.1 all core and it would get REALLY hot even when not under high loads.

The reason that lead me to get the Asrock wasn't valid anymore so I installed the Gigabyte again.
With PBO on, the cpu flies. Can't get it to run as fast as the 5800x in single core, but multi-core it went as high as 4.3Ghz and I believe it would run faster as it was thermally limited.

But in stock form... I'm really struggling to:

1. understand what performance to expect from the cpu as different tests online give different values;
2. what's up with the cpu clocks being lower with an higher infinity fabric speed?

First off thank you everyone for your time. I would like to discuss my findings with ryzen 2 and 3 Ram instability issues specifically with in the 8 core variants of both gens. But first time for some back story.

(Skip if you want to)

Early last summer my brother asked me to build him a new gaming PC. After his long running AMD FX PC was finally ready to kick the bucket Ryzen gen 2 was released for like a month at the time. I, whom already had built my own Ryzen + gaming rig wanted to go all AMD for him as well and what better timing as the new Ryzen 3000 and x570 boards already released. After the build was complete and handed off to my brother the PC was working great for several months, then early fall hit. The computer started shutting off randomly and restarting. Through out the months we have tried replacing the PSU, CPU, Motherboard, and RAM to no luck of fixing the issue. Windows being re installed and other things in the bios to get the computer stable to no avail. The issue of restarting with no BSOD or log to tell me what was wrong frustrated the hell out of me and wished id have just built him a Intel rig instead. Until finally i figured out what was the issue.

(Main Discussion)

So, Ram Stability in AMD 3000 and 5000 Ryzen chips specifically 8 core variants. After having random restarts after being stable for around 3 months, having replace the PSU, CPU, MOBO, and RAM either the Computer would restart or games/programs/apps would crash and have no logs. What i have figured out is the memory controller/ IF can be so sensitive at high frequency's if overloaded it will restart and or crash high demanding apps and worse start to break in. Here is the setup i was using and the parts i replaced them with and inter swapped to try and get them to work.

1st RIG:

ASROCK x570 steel legend micro ATX
AMD Ryzen 3700
Corsair 3600mhz RAM 2x8GB single rank 
AMD Radeon 5700xt
Seasonic 800Watt PSU

Parts Replaced with:

ASUS TUFF B550 Wifi micro ATX
AMD Ryzen 5800
Corsair 3200mhz RAM 2x8GB Single rank
EVGA 850Watt PSU

After many hardware swaps bios updating, changing settings and reading many many man other forums on random restarts i stubbled on a discussion of RAM RANKING. I know what ram ranking is and i personally seek out Dual Rank sticks for my own personal RIG before this issue occurd. This made me think to try a dual rank ram setup. Though the ram i purchased to replace the old was not dual ran

Hey, i have an Asrock A320m HDV R4 motherboard, ryzen 5 3400g with 2 sticks of 8gb team TUF gaming alliamce 3600mhz ram set by the XMP profile u/3600mhz but CPUZ says its running asynchronous and there's no infinity fabric or fclk option that i can see to obtain the 1:1 ratio

Using bios 4.00 as well

Any suggestions would be greatly appreciated

Edit: found another post a year ago with the same issue but no replies

https://www.reddit.com/r/AMDHelp/comments/cu0u7m/fsbdram_running_asynch_on_ryzen_embedded_v1605b/

https://reddit.com/link/o6bkqj/video/jkmtlvjfb0771/player

I had heard that you get an insane penalty by desynchronizing the infinity fabric on ryzen and for some reason the clock speeds are changing realtime.

I just posted this over in the AMD sub that I'm also active in, but wanted to share this here too because it might be of interest to some of my fellow AMD Ryzen users who are into overclocking their stuff.

TL:DR - I re-synched my IF at the 1:2 ratio which is the only other option my motherboard shows for Infinity Fabric to Memory Clock synchronization, the other option of course being 1:1. This allowed me to increase my RAM speed beyond the 3800 MT/s at 1:1 IF I'd been running for a few months now to see if I could get the RAM speed to be higher enough to overcome the latency penalties inherent in doing so, and then to see how different programs respond to that tradeoff. The former is now complete, the latter is ongoing.

Discussion: The conventional wisdom in AMD land is that for best performance the Infinity Fabric must always be 1:1 synched with the memory clock. "Everyone knows this!" We see this being said all the time, even used as a club in certain discussions in lieu of presenting actual data. After watching a Buildzoid video on Youtube a while back where he discussed this, and pointed out that if you can set your memory speed higher enough with de-synched (or rather synched at a worse ratio) IF it could still be an advantage to do so despite the higher latency.

I finally got around to trying this out. After ensuring I had my current bios profile safely stored off on a USB stick, I reset all my secondaries and tertiaries to Auto, reset my primaries to very sloppy settings up in the low 20s, and then started jacking up the memory clock. I booted successfully at 4266MT/s but failed to boot at 4400MT/s so I stopped at 4266. I didn't try any shenanigans to see if I could goose the machine into booting at 4400MT/s or higher with some more twiddling, so it's possible that through some further playing around those higher speeds could be achieved.

I then spent the next 4-5 hours dialing my primaries, secondaries, and tertiaries back down.

I stopped at 16-16-16-28 for the primaries. For completeness I should have attempted CL14, and may go back and do that. CL16 worked, and I just assumed that CL14 (same as I achieved at 3800) would be a bridge too far, so I didn't pursue it. I probably should.

Result: Here's my Zen timings for my 3800/14-15-15-28 profile that I had. Btw, I had intended to set those 15s to 14 and retest back when I was OCing my RAM and just never got back to doing

Hi guys,

Do I still need to put the infinity fabric at 1800mhz when ram is at 3600mhz? Or auto is now working fine?

Thank you.