Discussion After new BIOS install, RAM frequency affects bandwidth or power to onboard audio and USB

[JDA81]

My motherboard is the Asus Z170-A. For over a year I was using BIOS 2202 with no problems. I could run my RAM at 3000MHz without issue, perfectly stable. I used the XMP profile which set the DRAM voltage to 1.35v. I also overclock my CPU but that has no part in this story.

When I updated to 3703 because of the recent Spectre flaw, I noticed several issues right away. If I set my RAM to 3000MHz I get static in my audio. That's weird right? It's 100% reproducible. If I lower my voltage to 1.2v from 1.35v at 3000MHz, I can't even POST. (I confirmed this had no relation to the CPU by running that at stock speed and voltage)

The 2nd (related) issue is even weirder. So I played around a bit with various frequencies and voltages. I found I could run with perfect stability at 2666MHz at 1.2v. I did a Prime95 blend test and a full Windows Memory Diagnostic to confirm stability.

HOWEVER, if I play VR (Oculus, so I have 4 devices plugged in which use a lot of bandwidth and probably also a fair amount of power) within sometimes as short as 5 minutes, I'll get SEVERE interruptions on the USB devices, leading to major gameplay issues or even crashes. I can't confirm if it's power or bandwidth related, but it's almost certainly one of the two because the system is otherwise perfectly stable.

If I set my RAM down to 2100MHz it is perfectly stable in VR. I can play for hours, no problems at all.

Note, this all happened IMMEDIATELY after updating to the newest BIOS, so I know it's not the fault of anything else but Asus's BIOS. I also have eliminated all other factors because the issues are perfectly reproducible by setting my RAM to a higher frequency and changing no other factors. If it was DRAM voltage related, I'd understand, but I can have my DRAM at 1.2v and 2666 and it breaks and 1.2v at 2100 and it's perfect.

I'd love to hear if anyone has any idea why this is happening. If anyone knows a workaround for this issue, too, that'd be great. Thanks!

 

[VirtualLarry]

Would be interested to find out what your PSU Amperage on the +5VSB line is.

 

[JDA81]

Would be interested to find out what your PSU Amperage on the +5VSB line is.

My PSU is the EVGA SuperNOVA 650 GS (650W). The amps on +5Vsb is 2.5A.

Why do you think they would break the power management in the new BIOS? It worked fine earlier in the day before I installed the BIOS.

 

[George P]

JDA81,
You may or may not know by now that the BIOS updates released to mitigate the Spectre vulnerability were rushed & ill-advised; major manufacturers & tech experts are now advising people to not update their BIOS if they haven't already:
http://www.zdnet.com/article/intel-stop-firmware-patching-until-further-notice/
http://www.zdnet.com/article/spectr...l-intels-buggy-patch-new-bios-updates-coming/

Not only were the BIOS 'fixes' rushed, mitigating the Spectre Variant 2 'flaw' (the only one that the BIOS microcode updates apply to) is a radical shift in both low-level hardware and software interaction; i.e. the way the OS 'calls' the CPU for a given operation will require an entirely new approach to remove the potential vulnerabilities of Spectre; same with hardware level fixes (it has to do with speculative execution, which, in super simple terms keeps a routine in CPU cache after it is run, then either runs it again if called or dumps it if not called again; the 'fix' is to purge the cache and force a new call every time, adding a huge number of cycles & bandwidth usage through the system CPU - RAM - Storage).
https://www.computerworld.com/artic...t-slowdowns-and-antivirus-proves-crucial.html
http://www.zdnet.com/article/spectre-puts-the-brakes-on-cpu-need-for-speed/
https://newsroom.intel.com/news/fir...ial-performance-data-for-data-center-systems/

The upshot of all this is, with both the BIOS updates and OS updates, they aren't even close to responsibly sorting out how to handle this and are releasing 'garbage' fixes to mitigate a potential security vulnerability that hasn't even been exploited yet (that we know of). (Link with Linux expert arguing the 'garbage' nature of these early patches: http://www.zdnet.com/article/linux-...mb_featured&ftag=TRE-03-10aaa6b&bhid=13072600 )

The side effect of all this is far reaching and unpredictable, and could very well be the cause of your problems.

Also Windows had issues with OS updates and ASUS motherboards in their early releases (bottom link).

I work with audio on computers every day (with an ASUS mobo & Win 7 Pro SP1 64 bit); I've noticed funky audio artifacts when attempting to overclock my CPU / DRAM, so I run things at 'stock' speed. I run hardcore DAW recording / mixing / mastering / massive sample streaming w on the fly time stretching from 4 SSDs, etc.. & I have 2 UAD-2 add-on DSP cards, so there are a lot of variables. I managed to roll back the Microsoft patches since they slow down both CPU & SSD speeds, especially for older mobo / CPU combos like mine (P8Z77-V-Pro / i7-3770K / 16 GB G.Skill 12800 DDR3 Dram); & ASUS dealt with newer models first, so no new bios has been offered for my board (nor would I install it unless I knew it would not have adverse side effects). http://www.zdnet.com/article/micros...greatest-meltdown-spectre-performance-issues/

Your best bet is to see if you can roll your BIOS back to the earlier one; then wait for a confirmed new BIOS that has less (Much less) impact on your system.

BTW, even if you don't use Win 7 or even Windows, you might want to scan this article about problems with ASUS boards & 'Spectre / Meltdown' patches causing BSOD, etc: https://answers.microsoft.com/en-us...b4056894/c9b510b4-20b8-447c-adc6-cf99e021f861

 

[JDA81]

Hi George P,

First, thank you for your well thought out reply.

However, I'm aware of the rushed nature of the Spectre fix, and I know that's what's causing my problems. What I really wished to find was the root (technical) reason I may be suffering such problems and/or something I could personally do to mitigate the issues I have experienced - a different voltage setting, a different RAM timing, anything of this nature.

I'm a computer scientist so I'm also aware of the nature of the Spectre problem. I am surprised they could release anything approaching 'mitigation' of the problem in a few months time. I'm not so good as to understand how they can mitigate this issue without just creating extra nops before and after branches.

When you overclocked your CPU / RAM, you tested for stability and also found the audio problems? I really wonder what that can be related to if you are sure the voltage is the same (the frequency, if stable, should not cause EM interference. I am glad to hear I'm not the only one that has suffered this problem which shouldn't even occur. I'm assuming that since we both have Asus mobos that they have just completely botched voltage regulation with regards to their memory controllers. I had problems with the memory controller of this mobo on very early BIOSes too, so they certainly didn't do a perfect job with it, anyways.

Unfortunately, Asus has really locked out BIOS rollbacks lately. AFAIK, even the most circumventing tools, such as the American Megatrends BIOS writer and other such tools, cannot revert the BIOS anymore. Which means I'm stuck until Asus (never) gets around to fixing this issue.

Anyways, thanks again for replying. I should be happy I'm not one of those suffering from greater instability problems than I am.

 

[Elixer]

Unfortunately, Asus has really locked out BIOS rollbacks lately.

This doesn't work anymore? http://forum.hwbot.org/showthread.php?p=462739

 

[George P]

You don't have an older bios backup up anywhere? I've become a digital pack-rat after experiencing issues like this over the years (companies taking down older bios & chipset releases, etc.).
Just to clarify, I did not have audio problems after any Spectre update (I was fortunate to have a very recent backup that allowed me to reinstall pre-update); when I assembled my Asus based system in 2013, I messed around with overclocking, but I experienced audio problems - probably due to the huge number of methods my audio programs and hardware move the data around (several samplers with different methods for using memory; UAD-2 DSP cards with Sharc chips on them to process audio through dedicated 'plug-ins'; PCI based RME converters & the associated driver; DAW usage of both memory and multi-core CPU, etc.).
Actually I was just thinking of trying to overclock again, since the DAWs and drivers are newer. I might get better results. But Audio recording on a PC is a tradeoff between stability and getting as close to 'real-time' as possible, which is why turning of Speed-Step & C states makes a huge difference; sadly, with those off, the bios provides less options for overclocking!

I hope you figure it out, or with luck, they release a better bios update soon. If you're stuck with that bios, at least be glad that a company like ASUS will want to improve their 'fix' since they are all about high performance.

 

[JDA81]

A new BIOS came out a few days ago. I updated. Same issue.

What I have found, though, is if I up my PCH voltage I can mitigate the problems caused by the RAM frequency.

Again my problems are tied to RAM FREQUENCY, not RAM voltage. Unless more voltages go into RAM frequency than just DRAM voltage (someone could correct me on this if I am wrong).

Still doesn't completely resolve my problem because I need absolute stability out of my USB buses.

Is it safe to overvolt PCH?

I wish I knew what power supply rails went to which specific devices and which devices could drain voltage from which other devices. I didn't have any problems on the old BIOS, and upgrading to 3xxx immediately caused me to have problems, so while I don't think it's PSU related, it's definitely power related.

 

[JDA81]

I finally solved my issue thanks to a clever user on the Asus forum.

Something I did not know, upping RAM frequency, even if you don't touch DRAM voltage, WILL UP VCCIO & VCCSA (system agent) voltage if you have them on any auto / adaptive setting. If you don't have those two voltages locked down, your system will be delivering more volts to those components! This is something I didn't know and nobody told me (even when I explicitly asked on very technical forums, and here).

In my case, this user found VCCIO & VCCSA were getting a bit too much, and both this user & I were experiencing voltage droop on our PCH (south bridge) causing audio issues (onboard sound) and USB power failures (in both our cases, hampering VR usability (he's on Vive, I'm on Oculus)).

Thankfully I knew what VCCIO & VCCSA should be at on the old BIOS, so I actually volted them to BELOW that, which made my PCH voltage stable, and RAM is still stable.

So there's really a lot to unpack there, but be aware of this important element to changing RAM frequency.

As for myself, I can finally get back to using my RAM at DDR4-3000 speeds and stable VR experiences.

 

[clovitox]

I finally solved my issue thanks to a clever user on the Asus forum.

Something I did not know, upping RAM frequency, even if you don't touch DRAM voltage, WILL UP VCCIO & VCCSA (system agent) voltage if you have them on any auto / adaptive setting. If you don't have those two voltages locked down, your system will be delivering more volts to those components! This is something I didn't know and nobody told me (even when I explicitly asked on very technical forums, and here).

In my case, this user found VCCIO & VCCSA were getting a bit too much, and both this user & I were experiencing voltage droop on our PCH (south bridge) causing audio issues (onboard sound) and USB power failures (in both our cases, hampering VR usability (he's on Vive, I'm on Oculus)).

Thankfully I knew what VCCIO & VCCSA should be at on the old BIOS, so I actually volted them to BELOW that, which made my PCH voltage stable, and RAM is still stable.

So there's really a lot to unpack there, but be aware of this important element to changing RAM frequency.

As for myself, I can finally get back to using my RAM at DDR4-3000 speeds and stable VR experiences.

Hello, i have the same MOBO ASUS Z170-A and a ram rated for 3000MHZ, having the same audio issues and tried bumping PCH voltage up and it reduced the audio cracking but they are still present.
What are the VCCIO & VCCSA values you are using? as i also recently updated my bios, but i dont recall the old values.

 

[Furious_Styles]

Hello, i have the same MOBO ASUS Z170-A and a ram rated for 3000MHZ, having the same audio issues and tried bumping PCH voltage up and it reduced the audio cracking but they are still present.
What are the VCCIO & VCCSA values you are using? as i also recently updated my bios, but i dont recall the old values.

I don't know for sure but they are probably 1.05 for SA and 0.925 for I/O.

 

[clovitox]

I don't know for sure but they are probably 1.05 for SA and 0.925 for I/O.

Im trying to tweak them at the moment, right now I have them at around 1.08-1.1 and no issues, clearly fixing my audio cracking issues by 95%.
The ´´auto´´ function had values at arround 1.2-1.3 for both of them.

 

[Furious_Styles]

Im trying to tweak them at the moment, right now I have them at around 1.08-1.1 and no issues, clearly fixing my audio cracking issues by 95%.
The ´´auto´´ function had values at arround 1.2-1.3 for both of them.

Yeah lots of OCing guides would even say to lock them in to around what you have them set at to avoid the auto voltages getting pumped up and generating unwanted heat. Glad to see you're getting some good results!

 

[clovitox]

Yeah lots of OCing guides would even say to lock them in to around what you have them set at to avoid the auto voltages getting pumped up and generating unwanted heat. Glad to see you're getting some good results!

Yeah this post really helped me out! i was about to buy a new MOBO thinking mine was dying since i didnt found a solution until now. Im not going to OC my CPU for the moment (stock 3.9Ghz with CPU-Boost) since I dont have anything CPU-Heavy other than a few games.

Thank you very much!.