Z790-E Gaming Wifi: BIOS often hangs with Q-Code "bf" if front panel USB 3 is used

[Snafu42]

Hi,

when booting the ROG STRIX Z790-E Gaming Wifi BIOS 2503 with some device connected to a front panel USB 3 connector, boot may hang with Q-Code "bf".

The following Q-Code sequence occurs after yellow green Q-LED(BOOT) lit up:
98(Console input connect), 99(Super I/O init), 9C(USB detect), b4(USB hot plug) ...HANG...

The "b4" is likely infinite or at least longer than 5 minutes. Such problem never occurred with any of the other USB connectors (back panel, front panel USB 2, front panel USB C).

To avoid any side effects from my preferred settings, I did some extra tests with default (F5) BIOS settings. Here a result of 32 resets shown as a bit mask (0 = "bf", 1 = OK):
00011001101110110111100111011110
This result is not easily distinguishable from "coin flipping" 🙂

I'm aware that too long internal USB 3 cables and/or low cable+connector quality may introduce problems. But tests with Win11 and Linux (grml.org Live Linux) show no problems with these front panel USB 3 connectors. Hotplug always works. Raw read tests with dd show reasonable speeds, for example 450MB/s with a NVMe M.2 SSD behind a docking station. The Linux kernel log does not show any of the usual suspect entries which would indicate cable problems: frequent USB interface resets, I/O errors, ...

The BIOS should at least "timeout" the detection, it should never hang.

[Snafu42]

I repeated some tests with front panel USB 3.0 disconnected and an "ASUS" USB 3.0 bracket connected instead. The cables are much shorter but the results were similar: Frequent "bf" hangs in BIOS and again no problems with Win11 or Linux.

So I guess this is a BIOS bug related to the internal USB 3.0 connectors.

PS: The USB 3.0 bracket is an accessory from an ASUS P8Z68-V PRO bought 2011. This box still runs without problems with an i7-2600K (first MB+CPU, second PSU, third graphics card, forth HDD/SSD setup, Windows never reinstalled or reactivated).

[achugh]

Hi @Snafu42 I am sorry to hear about your issues. You mentioned that this problem is only happening with the Front Panel USB 3.0 connector

Such problem never occurred with any of the other USB connectors (back panel, front panel USB 2, front panel USB C).

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To me it seems the problem is related one of the three situations that come to my mind (there could be more that others maybe able to spot and help).

1. Since you are connecting a device which maybe drawing power from the USB cable, can you confirm if you have installed the Power Delivery Firmware update from your support page?
   1. I am referring to https://dlcdnets.asus.com/pub/ASUS/mb/LGA1700/ROG_STRIX_Z790-E_GAMING_WIFI/ASUS_PD_update_tool_V004.... firmware released on 11-July-2023 that is mentioned on https://rog.asus.com/motherboards/rog-strix/rog-strix-z790-e-gaming-wifi-model/helpdesk_bios/ page with label PD update tool
   2. Can you also share what is the exact make and model of the device giving you issues?
   3. It is possible that this device is requesting power that the board is not able to provide via the front panel connector. This leads to the next reason
2. If you have the latest Power Delivery firmware and you are still experiencing issues, it could be related to power delivery to this connected device.
   1. What is the exact make and model of your Power Supply Unit (PSU)?
   2. Have you connected BOTH the 12V ATX_12V_1 and ATX_12V_2 connectors in the top left corner of your board? These are 8-Pin connectors labeled #5 in your board's user manual on PAGE 1-2.
   3. In order to see how much power is being drawn by your USB device, you can add https://www.amazon.com/dp/B09T3KHBFL/ref=sspa_dk_detail_4?psc=1&pd_rd_i=B09T3KHBFL&pd_rd_w=qs6ks&con... type of a monitor device to see what is happening with power draw as a suggestion.
3. Finally, the last option that comes to my mind is that your device goes into some sleep states as part of power management and it is not waking up during the boot process.
   1. This would fall under device compatibility issues as USB devices which were once thought as the holly grail to solve consumer problems have become the most problematic devices and protocol to really understand for an everyday to enthusiastic consumers.
   2. I am not sure I will be able to help much here if this turns out to be your issue since this is where either ASUS or your device manufacturer will have to push a new firmware update to solve this compatibility issue.
   3. One way to bypass these issues as a workaround is to add a USB Hub in the middle because the new hub now acts as a bridge/proxy which can handle the USB requests on both sides to get around the direct compatibility issues. Adding a powered hub is another workaround to solve power delivery issues too. So there are options here but they require a good bit of trial and error.

I hope this information helps you move forward in your journey to finding the root cause and then potentially solving the issue.

[Snafu42]

Hi @achugh, thanks for the detailed hints.

1. PD update, devices
1. No, I didn't install the PD update. The single line release note "Fix wrong message when system resumes from S3 or S4." does neither suggest that this is important nor that this would solve my issue. Update now done. Unfortunately it does not change anything (BTW: If the Intel Serial IO driver is missing, this lousy update installer prints multiple useless lines twice and then stops without any useful message).
2. Here the list of devices I used for testing (measured 'idle' to 'dd raw read test' current range in parentheses). All devices triggered the issue several times:
   Flash drives: Kingston Data Traveler G3 64GB (70-105mA), SanDisk Ultra USB 3.0 32GB (90-200mA), SanDisk Ultra Luxe USB 3.2 512GB (30-130mA),
   SATA: Intel 520 behind Sharkoon SATA QuickPort USB 3.1 Type C (0mA).
   NVMe: Crucial T700 behind Sabrent Dual M.2 Docking Station USB 3.2 Gen 2 Type C (0mA)
3. Max current is always below USB 2.0 500mA limit, see above. Connecting devices for charging show reasonable Voltage drops. This suggest DC resistance of approx. 0.3ohm for front panel, 0.2ohm for USB 3 bracket and 0.1ohm for back panel.
2. PSU
1. PSU: BeQuiet Straight Power 12 850W. Many tests (P95, Cinebench, openssl speed, ...) which pushed the i7-14700K to its PL1/2=253W limit revealed no signs of trouble
2. Of course, BOTH ATX_12V are connected 🙂
3. I already have two different USB power meters and would also recommend the device you mentioned.
3. If there would be a problem with sleep states, multiple devices (see above) would have the same problem.

Fortunately the problem only happened on (re)boots but never on wakeup from standby (S3).

Thanks for any further hints.

[achugh]

Hi @Snafu42 have you tried to CLEAR CMOS followed by F5 to load defaults? If this does not work, have you tried any older BIOS to see if those are also exhibiting this same problem? You may need help from ASUS Care Team for this peculiar issue. Sorry, I am out of ideas. Good luck!

[Snafu42]

Hi @achugh, meantime I tried CLEAR CMOS, made no difference. The problem at least also appeared with previous BIOS 2402 and possibly also with 2301. I didn't test these connectors with the preinstalled version 1303.

I'll contact Asus support and report the result here.

[achugh]

Hi @Snafu42 ,

Please see https://rog-forum.asus.com/t5/intel-700-600-series/z790m-plus-will-not-go-into-standby-automatically... post. Do you have the latest Windows updates installed? Have you tried to RESET your power profile configuration in Windows to see if that helps to resolve your issue?

I am referring to running the following command from the Windows Command Prompt running as Administrator

powercfg -restoredefaultschemes

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[Snafu42 · Accepted solution]

After BIOS update from 2503 to 2703, the problem does no longer occur. I hope this situation persists 🙂