Lenovo Legion Go (8APU1) Error VIDEO_TDR_FAILURE (amdkmdag.sys): Legion Go APU TDR Crash
The AMD Ryzen Z1 Extreme APU experienced a Timeout Detection and Recovery (TDR) event triggered by thermal throttling under sustained TDP load (>30W), leading to kernel-mode graphics driver (amdkmdag.sys) desynchronization and a bugcheck 0x116.
Hardware Diagnostic Matrix
Spec Ref #ee605f1cRequired Diagnostic Tools & Instrumentation
Multimeter Probing Targets & Circuit Tolerances
Bench Calibrated ±5%| Test Point / Circuit | Target Nominal Spec | Expected State | Fault Condition |
|---|---|---|---|
| Main Logic DC Bus | 3.3V / 5.0V DC (±0.1V) | Stable DC Potential | <2.9V (Brownout / Sag) |
| Thermistor / NTC Sensor | 10kΩ - 100kΩ @ 25°C | Smooth Thermal Curve | 0Ω (Short) or ∞ (Open) |
| Safety Ground / PE Continuity | < 0.5Ω Resistance | Solid Earth Bond | > 1.0Ω (Floating Chassis) |
Common Symptoms & Fault Manifestations
- BSOD displaying VIDEO_TDR_FAILURE with failing module amdkmdag.sys during 3D gaming loads
- Extreme frame drops followed by display freeze while fan runs at maximum RPM
- APU hotspot temperature spikes to 100°C+ prior to black screen crash
- Display driver fails to recover, requiring a hard power cycle
Root Causes & System Failure Modes
Severe thermal dissipation failure caused by heatsink fin blockage, dried phase-change TIM, or heat pipe vapor leak exceeding TjMax (100°C)
VRAM/UMA frame buffer starvation due to corrupted AMD GPU microcode or conflicting Windows Update graphics drivers
Transient power drop on VDDCR_VDD/VDDCR_SOC rails under peak boost states during thermal de-rate
High-Voltage & Mechanical Safety Isolation
Prior to opening access panels, disconnecting terminals, or probing wiring, perform complete lock-out / tag-out (LOTO). Disconnect all AC mains, DC string isolators, and lithium battery banks. Allow internal smoothing capacitors at least 3 to 5 minutes to dissipate stored residual energy below safe threshold (<30VDC).
Step-by-Step Diagnostic & Resolution Procedure
Safe Isolation and BIOS Power Cut
Boot into BIOS (Hold Volume Up + Power). Navigate to Configuration > Disable Building-in Battery. Confirm shutdown and disconnect the 65W USB-PD adapter to safely de-energize the motherboard.
Clean Driver Sanitization (Software Phase)
Reboot into Windows Safe Mode. Run Display Driver Uninstaller (DDU) to wipe all AMD display drivers and registry paths. Reboot and install the official Lenovo-certified AMD graphics driver package (OEM branch), setting UMA Frame Buffer Size in BIOS to 6G.
Thermal Subsystem Inspection & Repaste
Remove back cover (6x Phillips screws). Disconnect battery cable. Unscrew the single cooling fan and copper heat pipe assembly. Clean factory thermal material with 99.9% IPA. Clear dust lint from radiator exhaust fins. Apply a pre-cut Honeywell PTM7950 phase-change pad over the Z1 Extreme APU die and re-torque screws in cross pattern.
Thermal Verification and Stress Test
Reassemble chassis and plug in AC adapter to wake the battery controller. Set OS Power Mode to 'Performance' and Thermal Mode to 'Custom 30W' with Full Fan curve in Legion Space. Run 3DMark Time Spy or FurMark for 20 minutes while monitoring HWiNFO64 to verify APU temperature remains below 88°C without TDR events.
Hardware Reset & Fault Clear Sequence
Controller ProcedurePrevention & Routine Maintenance Guidelines
- Set Windows Update policy to prevent automatic overwriting of OEM AMD graphics drivers
- Avoid running 30W Custom TDP continuously on soft surfaces that block rear intake grilles
- Clean fan exhaust vents with compressed air every 3 months to prevent lint buildup
Frequently Asked Diagnostic Questions
What does error code VIDEO_TDR_FAILURE (amdkmdag.sys) indicate on Lenovo Legion Go (8APU1)?
The AMD Ryzen Z1 Extreme APU experienced a Timeout Detection and Recovery (TDR) event triggered by thermal throttling under sustained TDP load (>30W), leading to kernel-mode graphics driver (amdkmdag.sys) desynchronization and a bugcheck 0x116. In engineering telemetry, it indicates legion go apu tdr crash requiring circuit verification.
What are the primary triggers causing error VIDEO_TDR_FAILURE (amdkmdag.sys)?
Diagnostic bench telemetry isolates the following common root causes: Severe thermal dissipation failure caused by heatsink fin blockage, dried phase-change TIM, or heat pipe vapor leak exceeding TjMax (100°C); VRAM/UMA frame buffer starvation due to corrupted AMD GPU microcode or conflicting Windows Update graphics drivers; Transient power drop on VDDCR_VDD/VDDCR_SOC rails under peak boost states during thermal de-rate.
How do I reset and clear Lenovo error VIDEO_TDR_FAILURE (amdkmdag.sys)?
Perform an EC (Embedded Controller) reset: Power down the Legion Go completely. Disconnect the charger. Hold the Power button continuously for 30 seconds until the LED indicators cycle off and on, releasing to reset platform power thresholds. If the error status repeats immediately after clearing, discontinue clearing and test circuit continuity.
Can I safely resolve error VIDEO_TDR_FAILURE (amdkmdag.sys) without specialized shop tooling?
This fault is graded as Intermediate difficulty with High severity. Standard diagnostics require an insulated digital multimeter and appropriate hand tools. Always observe high-voltage isolation procedures.