diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index d9b50ee..acaaf42 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -6,7 +6,7 @@ on:
   workflow_dispatch:
 
 env:
-  QT_VERSION: '6.5.3'
+  QT_VERSION: '6.8.3'
   QT_ARCH: 'win64_msvc2019_64'
 
 jobs:
@@ -63,8 +63,8 @@ jobs:
             boost_1_85_0
             svgpp-1.3.1
             ngspice-42
-          key: deps-manual-v1-${{ runner.os }}
-
+          key: deps-manual-v1-${{ runner.os }}-qt-${{ env.QT_VERSION }}
+          
       # ── 4. Build ZLib ─────────────────────────────────────────────────────
       - name: Download ZLib
         if: steps.deps-cache.outputs.cache-hit != 'true'