From 883f24d149335c3fc2745a9d1e6094000f9aea28 Mon Sep 17 00:00:00 2001
From: Blacktempel <6657796+Blacktempel@users.noreply.github.com>
Date: Fri, 30 Jan 2026 10:58:22 +0100
Subject: [PATCH] Add Pump Fan 2 for MSI MEG Z790 GODLIKE MAX + handle 0 RPM /
 unplugged fan (#2187)

* Add Pump Fan 2.
Handle Fan at 0 RPM or unplugged.

* Space
---
 .../Hardware/Motherboard/Lpc/Nct677X.cs          | 16 ++++++++++++----
 .../Hardware/Motherboard/SuperIOHardware.cs      |  3 ++-
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/Nct677X.cs b/LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/Nct677X.cs
index f55c7be..4ab37cc 100644
--- a/LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/Nct677X.cs
+++ b/LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/Nct677X.cs
@@ -401,7 +401,7 @@ internal class Nct677X : ISuperIO
             case Chip.NCT6683D:
             case Chip.NCT6686D:
             case Chip.NCT6687D:
-                Fans = new float?[17];
+                Fans = new float?[18];
                 Controls = new float?[8];
                 Voltages = new float?[14];
                 Temperatures = new float?[11];
@@ -462,11 +462,12 @@ internal class Nct677X : ISuperIO
                 // SYS Fan 3 on newer NCT6687Ds
                 // SYS Fan 2 on newer NCT6687Ds
                 // SYS Fan 1 on newer NCT6687Ds
+                // PUMP Fan 2 on some NCT6687Ds - 0x850 (e.g. Z790 GODLIKE MAX)
                 // SYS Fan 7 on some NCT6687Ds - 0x852 (e.g. Z790 GODLIKE MAX)
-                _fanRpmRegister = [0x140, 0x142, 0x144, 0x146, 0x148, 0x14A, 0x14C, 0x14E, 0x150, 0x152, 0x154, 0x156, 0x158, 0x15A, 0x15C, 0x15E, 0x852];
+                _fanRpmRegister = [0x140, 0x142, 0x144, 0x146, 0x148, 0x14A, 0x14C, 0x14E, 0x150, 0x152, 0x154, 0x156, 0x158, 0x15A, 0x15C, 0x15E, 0x850, 0x852];
 
-                // On some boards, there will be SYS Fan 7 (e.g. MSI MEG Z790 GODLIKE MAX)
-                _fanCountRegister = [0x852];
+                // On some boards, there will be PUMP Fan 2 and SYS Fan 7 (e.g. MSI MEG Z790 GODLIKE MAX)
+                _fanCountRegister = [0x850, 0x852];
 
                 // max value for 13-bit fan counter
                 _maxFanCount = 0x1FFF;
@@ -840,6 +841,13 @@ internal class Nct677X : ISuperIO
 
         void Update13BitFan(int i, byte low, byte high)
         {
+            // No fan plugged in OR fan is at 0 RPM
+            if (Chip is Chip.NCT6687D && high == 0xFF && low == 0xF8)
+            {
+                Fans[i] = 0;
+                return;
+            }
+
             int count = (high << 5) | (low & 0x1F);
             if (count < _maxFanCount)
             {
diff --git a/LibreHardwareMonitorLib/Hardware/Motherboard/SuperIOHardware.cs b/LibreHardwareMonitorLib/Hardware/Motherboard/SuperIOHardware.cs
index a3839ed..b603ca4 100644
--- a/LibreHardwareMonitorLib/Hardware/Motherboard/SuperIOHardware.cs
+++ b/LibreHardwareMonitorLib/Hardware/Motherboard/SuperIOHardware.cs
@@ -559,13 +559,14 @@ internal sealed class SuperIOHardware : Hardware
 
                         f.Add(new Fan("CPU Fan", 0));
                         f.Add(new Fan("Pump Fan #1", 1));
+                        f.Add(new Fan("Pump Fan #2", 16));
                         f.Add(new Fan("System Fan #1", 2));
                         f.Add(new Fan("System Fan #2", 3));
                         f.Add(new Fan("System Fan #3", 4));
                         f.Add(new Fan("System Fan #4", 5));
                         f.Add(new Fan("System Fan #5", 6));
                         f.Add(new Fan("System Fan #6", 7));
-                        f.Add(new Fan("System Fan #7", 16));
+                        f.Add(new Fan("System Fan #7", 17));
 
                         c.Add(new Control("CPU Fan", 0));
                         c.Add(new Control("Pump Fan #1", 1));