diff --git a/install.sh b/install.sh
index d5498e7f7a..ea77ecd4d9 100755
--- a/install.sh
+++ b/install.sh
@@ -2225,9 +2225,20 @@ _torch_index_repairable() {
 #   <venv_dir>/.unsloth-torch-index   (single line = the resolved index URL)
 _TORCH_INDEX_MARKER_NAME=".unsloth-torch-index"
 
+# Lowercase ONLY a known wheel-family leaf (rocm* / gfx* / cpu / cuXXX); a custom
+# mirror leaf keeps its case so a verbatim URL pin is not falsely matched equal.
+# Mirrors _normalize_family_leaf in install_python_stack.py / setup.ps1.
+_normalize_family_leaf() {
+    _l_low=$(printf '%s' "$1" | tr '[:upper:]' '[:lower:]')
+    case "$_l_low" in
+        rocm*|gfx*|cpu|cu[0-9]*) printf '%s' "$_l_low" ;;
+        *) printf '%s' "$1" ;;
+    esac
+}
+
 # Normalise a wheel index URL for exact marker/pin comparison: trim whitespace,
-# strip ALL trailing slashes, lowercase ONLY the final path segment (the leaf).
-# Mirrors _normalize_index_url in install_python_stack.py / setup.ps1 / install.ps1.
+# strip ALL trailing slashes, lowercase ONLY a known-family final path segment.
+# Mirrors _normalize_index_url in install_python_stack.py / setup.ps1.
 _normalize_index_url() {
     _n_url="$1"
     # Trim leading/trailing whitespace.
@@ -2240,11 +2251,11 @@ _normalize_index_url() {
         */*)
             _n_head="${_n_url%/*}"
             _n_leaf="${_n_url##*/}"
-            _n_leaf=$(printf '%s' "$_n_leaf" | tr '[:upper:]' '[:lower:]')
+            _n_leaf=$(_normalize_family_leaf "$_n_leaf")
             printf '%s/%s' "$_n_head" "$_n_leaf"
             ;;
         *)
-            printf '%s' "$_n_url" | tr '[:upper:]' '[:lower:]'
+            _normalize_family_leaf "$_n_url"
             ;;
     esac
 }
@@ -3098,6 +3109,13 @@ elif [ -n "$TORCH_INDEX_URL" ]; then
                         "$TORCH_CONSTRAINT" "$TORCHVISION_CONSTRAINT" "$TORCHAUDIO_CONSTRAINT" \
                         --index-url "$TORCH_INDEX_URL" \
                         --force-reinstall
+                    # The repair reinstalled torch from $TORCH_INDEX_URL (the generic
+                    # ROCm index), not the Radeon --find-links repo, so record THAT as
+                    # the marker source. A Radeon --find-links install set
+                    # _TORCH_MARKER_INDEX_URL to its repo.radeon.com base earlier;
+                    # leaving it would make the marker misreport Radeon wheels and let a
+                    # later Radeon pin compare-equal and skip a needed reinstall.
+                    _TORCH_MARKER_INDEX_URL="$TORCH_INDEX_URL"
                 fi
                 ;;
         esac
diff --git a/studio/install_python_stack.py b/studio/install_python_stack.py
index d5b0aa15af..b68aebb328 100644
--- a/studio/install_python_stack.py
+++ b/studio/install_python_stack.py
@@ -137,15 +137,31 @@ _PYTORCH_WHL_BASE = (
 _TORCH_INDEX_MARKER_NAME = ".unsloth-torch-index"
 
 
+def _normalize_family_leaf(leaf: str) -> str:
+    """Lowercase ONLY a known wheel-family leaf (rocm* / gfx* / cpu / cuXXX).
+
+    The canonical gfx120X-all (capital X) must match AMD's lowercase gfx120x-all, so
+    known-family leaves are lowercased. A custom mirror leaf (/Current, /simple, ...)
+    keeps its case: an unknown-family URL pin is applied verbatim, so /Current and
+    /current must NOT compare equal. Same known-family set as
+    _explicit_unknown_family_torch_index_url. Mirrors the gate in install.sh /
+    setup.ps1. Pure function.
+    """
+    low = leaf.lower()
+    if low.startswith(("rocm", "gfx")) or low == "cpu" or re.match(r"^cu[0-9]", low):
+        return low
+    return leaf
+
+
 def _normalize_index_url(url: "str | None") -> "str | None":
     """Canonicalise a wheel index URL for exact marker/pin comparison.
 
-    Trims surrounding whitespace, strips ALL trailing slashes, and lowercases only
-    the FINAL path segment (the wheel-family leaf: cu128 / cpu / rocm7.2 / gfx1151 /
-    gfx120X-all). The host part is left untouched (it may be case-sensitive on some
-    mirrors); the leaf is lowercased so the canonical gfx120X-all (capital X) and
-    AMD's lowercase pip leaf gfx120x-all compare equal. MUST match the same
-    normalization in install.sh / setup.ps1 / install.ps1. Returns None for an
+    Trims surrounding whitespace, strips ALL trailing slashes, and lowercases the
+    FINAL path segment ONLY when it is a known wheel-family leaf (cu128 / cpu /
+    rocm7.2 / gfx1151 / gfx120X-all) -- see _normalize_family_leaf. The host part is
+    left untouched (case-sensitive on some mirrors), and a custom (unknown-family)
+    leaf keeps its case so a verbatim URL pin is not falsely matched equal. MUST
+    match the same normalization in install.sh / setup.ps1. Returns None for an
     empty/whitespace-only input. Pure function.
     """
     if url is None:
@@ -158,8 +174,8 @@ def _normalize_index_url(url: "str | None") -> "str | None":
         return None
     head, sep, leaf = url.rpartition("/")
     if sep:
-        return f"{head}/{leaf.lower()}"
-    return url.lower()
+        return f"{head}/{_normalize_family_leaf(leaf)}"
+    return _normalize_family_leaf(url)
 
 
 def _torch_index_marker_path() -> Path:
@@ -1504,6 +1520,13 @@ def _ensure_cuda_torch() -> None:
         # build simply re-lands on the same family (idempotent).
         _installed_desc = _installed_cu if _installed_cu else "an untagged CUDA build"
         _why = f"torch is {_installed_desc} but the pinned CUDA index is {_pin_leaf}"
+    elif _marker == "cuda" and _pinned_cuda and _marker_pin_mismatch(_pin) is True:
+        # Same cuXXX leaf but the marker records a DIFFERENT full index URL (e.g. the
+        # official cu128 index vs an internal mirror's cu128). The +cuXXX tag cannot
+        # see the host change, so consult the exact-URL marker and reinstall from the
+        # pinned URL (via _detect_cuda_torch_index_url, which honours the override) so
+        # an explicit mirror pin is applied and re-recorded, not skipped.
+        _why = f"the pinned CUDA index URL differs from the recorded marker (leaf {_pin_leaf})"
     else:
         return  # healthy CUDA torch matching the pin, or a deliberate CPU wheel
 
diff --git a/studio/setup.ps1 b/studio/setup.ps1
index 2c865d7056..b05dcf2ff9 100644
--- a/studio/setup.ps1
+++ b/studio/setup.ps1
@@ -436,16 +436,26 @@ $TorchIndexMarkerName = ".unsloth-torch-index"
 
 # Normalise a wheel index URL for exact marker/pin comparison: trim whitespace,
 # strip ALL trailing slashes, lowercase ONLY the final path segment (the leaf).
-# Mirrors _normalize_index_url in install.sh / install_python_stack.py / install.ps1.
+# Lowercase ONLY a known wheel-family leaf (rocm* / gfx* / cpu / cuXXX); a custom
+# mirror leaf keeps its case so a verbatim URL pin is not falsely matched equal.
+# Mirrors _normalize_family_leaf in install.sh / install_python_stack.py.
+function Get-NormalizedFamilyLeaf {
+    param([string]$Leaf)
+    $low = $Leaf.ToLowerInvariant()
+    if ($low -match '^(rocm|gfx)' -or $low -eq 'cpu' -or $low -match '^cu[0-9]') { return $low }
+    return $Leaf
+}
+
+# Mirrors _normalize_index_url in install.sh / install_python_stack.py.
 function Get-NormalizedIndexUrl {
     param([string]$Url)
     if ([string]::IsNullOrWhiteSpace($Url)) { return $null }
     $u = $Url.Trim().TrimEnd('/')
     if ([string]::IsNullOrWhiteSpace($u)) { return $null }
     $idx = $u.LastIndexOf('/')
-    if ($idx -lt 0) { return $u.ToLowerInvariant() }
+    if ($idx -lt 0) { return (Get-NormalizedFamilyLeaf $u) }
     $head = $u.Substring(0, $idx)
-    $leaf = $u.Substring($idx + 1).ToLowerInvariant()
+    $leaf = Get-NormalizedFamilyLeaf ($u.Substring($idx + 1))
     return "$head/$leaf"
 }
 
diff --git a/tests/sh/test_torch_index_marker.sh b/tests/sh/test_torch_index_marker.sh
index c8f63a5dc7..ad7b1512da 100755
--- a/tests/sh/test_torch_index_marker.sh
+++ b/tests/sh/test_torch_index_marker.sh
@@ -18,6 +18,8 @@ _TORCH_INDEX_MARKER_NAME=".unsloth-torch-index"
 # Extract the marker helpers from install.sh and source them.
 _FUNC_FILE=$(mktemp)
 {
+    sed -n '/^_normalize_family_leaf()/,/^}/p' "$INSTALL_SH"
+    echo ""
     sed -n '/^_normalize_index_url()/,/^}/p' "$INSTALL_SH"
     echo ""
     sed -n '/^_write_torch_index_marker()/,/^}/p' "$INSTALL_SH"
@@ -42,8 +44,8 @@ assert_eq "trailing slashes stripped + leaf lowered" \
 assert_eq "whitespace trimmed" \
     "https://download.pytorch.org/whl/cu128" \
     "$(_normalize_index_url '  https://download.pytorch.org/whl/cu128  ')"
-assert_eq "host case preserved, only leaf lowered" \
-    "https://Mirror.Local/simple" \
+assert_eq "host + custom (unknown-family) leaf case preserved" \
+    "https://Mirror.Local/Simple" \
     "$(_normalize_index_url 'https://Mirror.Local/Simple/')"
 # gfx120X-all (capital X) and AMD's lowercase pip leaf normalise equal.
 assert_eq "gfx120X-all == gfx120x-all after normalize" \
diff --git a/tests/studio/install/test_rocm_support.py b/tests/studio/install/test_rocm_support.py
index 10d198fd85..45b819f98f 100644
--- a/tests/studio/install/test_rocm_support.py
+++ b/tests/studio/install/test_rocm_support.py
@@ -1016,8 +1016,11 @@ class TestTorchIndexMarkerHelpers:
         assert f("https://repo.amd.com/rocm/whl/gfx120X-all///") == (
             "https://repo.amd.com/rocm/whl/gfx120x-all"
         )
-        # Host case preserved (only the leaf is lowered).
-        assert f("https://Mirror.Local/Simple/") == "https://Mirror.Local/simple"
+        # Host case preserved; a custom (unknown-family) leaf keeps its case so a
+        # verbatim URL pin is not falsely matched equal (only known families lower).
+        assert f("https://Mirror.Local/Simple/") == "https://Mirror.Local/Simple"
+        # A custom mirror leaf differing only in case must NOT compare equal.
+        assert f("https://mirror.local/Current") != f("https://mirror.local/current")
         # Whitespace trimmed.
         assert f("  https://download.pytorch.org/whl/cu128  ") == (
             "https://download.pytorch.org/whl/cu128"