The mid-June BIOS update (Q7CN78WW) for the Lenovo Legion Pro 7 Gen 10 (Model: 16IAX10H) introduces an aggressive Active State Power Management (ASPM) bug that drops NVMe SSDs off the PCIe bus, causing 0x154 UNEXPECTED_STORE_EXCEPTION crashes. Because Lenovo hardware-locked BIOS rollbacks via Intel Boot Guard, the permanent solution requires a two-pronged approach: manually disabling Windows PCIe Link State Power Management, and deploying an automated batch script that forces hidden NVMe latency tolerances to zero to prevent the drives from entering unstable deep-sleep states. Spent two weeks changing parts and troubleshooting to finally pin this down.

The Symptoms

If you are running the 16IAX10H chassis (Intel Core Ultra 9) and experiencing this bug, your system will show the following behaviors:

• The Crash: Random errors are 0x154 UNEXPECTED_STORE_EXCEPTION, alongside 0x3B SYSTEM_SERVICE_EXCEPTION and 0x50 PAGE_FAULT_IN_NONPAGED_AREA BSODs, typically occurring during load transitions in games or while running in Balanced (White) or Quiet (Blue) modes or even Extreme mode.
• The 0% Dump: The BSOD crash dump progress (MAY) stays stuck at 0%. This happens because the SSD has electrically vanished from the bus; Windows cannot write the log file.
• Performance Mode Immunity: The system is 100% stable when running in Performance Mode (Red LED) because this mode natively locks the PCIe bus in a high-power active state ($L0$).

The Root Cause Analysis

Based on cross-referencing global hardware communities (including Chinese Y9000P and Korean Legion forums), this is a synergistic failure of firmware and physical constraints on the Gen 10 motherboard:

1. Firmware (Primary): The Q7CN78WW BIOS altered Intel DTT profiles to save power on Arrow Lake-HX CPUs, aggressively forcing the M.2 slots into $D3_{cold}$ / $L1.2$ sleep states. When a game demands sudden I/O, the SSD controller fails the power-state transition fast enough, triggering a Windows driver timeout.

The Permanent Fix

Do not attempt a BIOS downgrade—Intel Boot Guard will block it ("signed bios guard secure image" error). You must modify the Windows power configurations and automate a script to ensure Lenovo Vantage does not override your settings when switching performance profiles.

Step 1: Disable PCIe Link State Power Management

This prevents Windows from allowing the M.2 slot to enter the unstable sleep states forced by the new BIOS.

1. Press Win + R, type control powercfg.cpl, and press Enter.
2. Click Change plan settings next to your active power plan, then click Change advanced power settings.
3. Expand PCI Express $\to$ Link State Power Management.
4. Set both On battery and Plugged in to Off.
5. Click Apply and OK. (Note: You must repeat this for any other power plans you use).

Step 2: Create the APST Override Batch File

1. Open Notepad.
2. Copy and paste the following code block exactly:

DOS

 off
for /f "tokens=4" %%i in ('powercfg /list ^| findstr "GUID"') do (
    powercfg /setacvalueindex %%i SUB_DISK d639518a-e56d-4345-8af2-b9f32fb26109 0
    powercfg /setdcvalueindex %%i SUB_DISK d639518a-e56d-4345-8af2-b9f32fb26109 0
    powercfg /setacvalueindex %%i SUB_DISK fc95af4d-40e7-4b6d-835a-56d131dbc80e 0
    powercfg /setdcvalueindex %%i SUB_DISK fc95af4d-40e7-4b6d-835a-56d131dbc80e 0
    powercfg /setacvalueindex %%i SUB_DISK d3d55efd-c1ff-424e-9dc3-441be7833010 0
    powercfg /setdcvalueindex %%i SUB_DISK d3d55efd-c1ff-424e-9dc3-441be7833010 0
    powercfg /setacvalueindex %%i SUB_DISK dbc9e238-6de9-49e3-92cd-8c2b4946b472 0
    powercfg /setdcvalueindex %%i SUB_DISK dbc9e238-6de9-49e3-92cd-8c2b4946b472 0
)
powercfg /setactive scheme_current

1. Save the file as NVMe_Fix.bat directly to the root of your C:\ drive.

Step 3: Automate via Task Scheduler

1. Search Windows for Task Scheduler and open it.
2. Click Create Task... (Not Basic Task).
3. General Tab: Name it NVMe Powercfg Fix. Check Run with highest privileges and check Hidden. Configure for Windows 10.
4. Triggers Tab: Click New. Set "Begin the task" to At log on.
5. Actions Tab: Click New. Action is Start a program. Browse and select C:\NVMe_Fix.bat.
6. Conditions Tab (Critical): Uncheck both AC power and battery power conditions so it runs regardless of being plugged in.
7. Settings Tab: Check Run task as soon as possible after a scheduled start is missed. Uncheck Stop the task if it runs longer than 3 days.
8. Click OK to save.

The mid-June BIOS update (Q7CN78WW) for the Lenovo Legion Pro 7 Gen 10 (Model: 16IAX10H) introduces an aggressive Active State Power Management (ASPM) bug that drops NVMe SSDs off the PCIe bus, causing 0x154 UNEXPECTED_STORE_EXCEPTION crashes. Because Lenovo hardware-locked BIOS rollbacks via Intel Boot Guard, the permanent solution requires a two-pronged approach: manually disabling Windows PCIe Link State Power Management, and deploying an automated batch script that forces hidden NVMe latency tolerances to zero to prevent the drives from entering unstable deep-sleep states. Spent two weeks changing parts and troubleshooting to finally pin this down.

The Symptoms

If you are running the 16IAX10H chassis (Intel Core Ultra 9) and experiencing this bug, your system will show the following behaviors:

• The Crash: Random errors are 0x154 UNEXPECTED_STORE_EXCEPTION, alongside 0x3B SYSTEM_SERVICE_EXCEPTION and 0x50 PAGE_FAULT_IN_NONPAGED_AREA BSODs, typically occurring during load transitions in games or while running in Balanced (White) or Quiet (Blue) modes or even Extreme mode.
• The 0% Dump: The BSOD crash dump progress (MAY) stays stuck at 0%. This happens because the SSD has electrically vanished from the bus; Windows cannot write the log file.
• Performance Mode Immunity: The system is 100% stable when running in Performance Mode (Red LED) because this mode natively locks the PCIe bus in a high-power active state ($L0$).

The Root Cause Analysis

Based on cross-referencing global hardware communities (including Chinese Y9000P and Korean Legion forums), this is a synergistic failure of firmware and physical constraints on the Gen 10 motherboard:

1. Firmware (Primary): The Q7CN78WW BIOS altered Intel DTT profiles to save power on Arrow Lake-HX CPUs, aggressively forcing the M.2 slots into $D3_{cold}$ / $L1.2$ sleep states. When a game demands sudden I/O, the SSD controller fails the power-state transition fast enough, triggering a Windows driver timeout.

The Permanent Fix

Do not attempt a BIOS downgrade—Intel Boot Guard will block it ("signed bios guard secure image" error). You must modify the Windows power configurations and automate a script to ensure Lenovo Vantage does not override your settings when switching performance profiles.

Step 1: Disable PCIe Link State Power Management

This prevents Windows from allowing the M.2 slot to enter the unstable sleep states forced by the new BIOS.

1. Press Win + R, type control powercfg.cpl, and press Enter.
2. Click Change plan settings next to your active power plan, then click Change advanced power settings.
3. Expand PCI Express $\to$ Link State Power Management.
4. Set both On battery and Plugged in to Off.
5. Click Apply and OK. (Note: You must repeat this for any other power plans you use).

Step 2: Create the APST Override Batch File

1. Open Notepad.
2. Copy and paste the following code block exactly:

DOS

u/echo off
for /f "tokens=4" %%i in ('powercfg /list ^| findstr "GUID"') do (
    powercfg /setacvalueindex %%i SUB_DISK d639518a-e56d-4345-8af2-b9f32fb26109 0
    powercfg /setdcvalueindex %%i SUB_DISK d639518a-e56d-4345-8af2-b9f32fb26109 0
    powercfg /setacvalueindex %%i SUB_DISK fc95af4d-40e7-4b6d-835a-56d131dbc80e 0
    powercfg /setdcvalueindex %%i SUB_DISK fc95af4d-40e7-4b6d-835a-56d131dbc80e 0
    powercfg /setacvalueindex %%i SUB_DISK d3d55efd-c1ff-424e-9dc3-441be7833010 0
    powercfg /setdcvalueindex %%i SUB_DISK d3d55efd-c1ff-424e-9dc3-441be7833010 0
    powercfg /setacvalueindex %%i SUB_DISK dbc9e238-6de9-49e3-92cd-8c2b4946b472 0
    powercfg /setdcvalueindex %%i SUB_DISK dbc9e238-6de9-49e3-92cd-8c2b4946b472 0
)
powercfg /setactive scheme_current

1. Save the file as NVMe_Fix.bat directly to the root of your C:\ drive.

Step 3: Automate via Task Scheduler

1. Search Windows for Task Scheduler and open it.
2. Click Create Task... (Not Basic Task).
3. General Tab: Name it NVMe Powercfg Fix. Check Run with highest privileges and check Hidden. Configure for Windows 10.
4. Triggers Tab: Click New. Set "Begin the task" to At log on.
5. Actions Tab: Click New. Action is Start a program. Browse and select C:\NVMe_Fix.bat.
6. Conditions Tab (Critical): Uncheck both AC power and battery power conditions so it runs regardless of being plugged in.
7. Settings Tab: Check Run task as soon as possible after a scheduled start is missed. Uncheck Stop the task if it runs longer than 3 days.
8. Click OK to save.