diff --git a/install.ps1 b/install.ps1
index a525d4df56..9e7913468f 100644
--- a/install.ps1
+++ b/install.ps1
@@ -2014,7 +2014,14 @@ exit 0
             # Accept both spellings so we don't fall through to the cu126 default.
             if ($output -match 'CUDA(?: UMD)? Version:\s+(\d+)\.(\d+)') {
                 $major = [int]$Matches[1]; $minor = [int]$Matches[2]
-                if ($major -ge 13)                    { return "$baseUrl/cu130" }
+                if ($major -ge 13) {
+                    # cu130 dropped Volta (sm_70/sm_72); cap V100s to cu128.
+                    $cap = (& $NvidiaSmiExe --query-gpu=compute_cap --format=csv,noheader 2>$null |
+                        ForEach-Object { $_.Trim() } | Where-Object { $_ -match '^\d+\.\d+$' } |
+                        Sort-Object { [version]$_ } | Select-Object -First 1)
+                    if ($cap -eq '7.0' -or $cap -eq '7.2') { return "$baseUrl/cu128" }
+                    return "$baseUrl/cu130"
+                }
                 if ($major -eq 12 -and $minor -ge 8)  { return "$baseUrl/cu128" }
                 if ($major -eq 12 -and $minor -ge 6)  { return "$baseUrl/cu126" }
                 if ($major -ge 12) { return "$baseUrl/cu124" }
diff --git a/install.sh b/install.sh
index 0acccdf049..9d48d716ad 100755
--- a/install.sh
+++ b/install.sh
@@ -2260,7 +2260,13 @@ get_torch_index_url() {
     fi
     _major=${_cuda_ver%%.*}
     _minor=${_cuda_ver#*.}
-    if [ "$_major" -ge 13 ]; then echo "$_base/cu130"
+    if [ "$_major" -ge 13 ]; then
+        # cu130 dropped Volta (sm_70/sm_72). A CUDA 13 driver still runs V100s,
+        # so cap Volta GPUs to cu128 (last wheels shipping sm_70). awk picks the
+        # lowest compute capability across GPUs (no tr/sort/grep dependency).
+        _min_cap=$(LC_ALL=C $_smi --query-gpu=compute_cap --format=csv,noheader 2>/dev/null \
+            | awk '{gsub(/[ \r]/,"")} /^[0-9]+\.[0-9]+$/{split($0,a,"."); v=a[1]*100+a[2]; if(m==""||v<m){m=v;c=$0}} END{if(c!="")print c}')
+        case "$_min_cap" in 7.0|7.2) echo "$_base/cu128" ;; *) echo "$_base/cu130" ;; esac
     elif [ "$_major" -eq 12 ] && [ "$_minor" -ge 8 ]; then echo "$_base/cu128"
     elif [ "$_major" -eq 12 ] && [ "$_minor" -ge 6 ]; then echo "$_base/cu126"
     elif [ "$_major" -ge 12 ]; then echo "$_base/cu124"
diff --git a/studio/setup.ps1 b/studio/setup.ps1
index f523b9ff14..2ce55593e7 100644
--- a/studio/setup.ps1
+++ b/studio/setup.ps1
@@ -419,7 +419,14 @@ function Get-PytorchCudaTag {
             $major = [int]$Matches[1]
             $minor = [int]$Matches[2]
             # PyTorch 2.10 offers: cu124, cu126, cu128, cu130
-            if ($major -ge 13) { return "cu130" }
+            if ($major -ge 13) {
+                # cu130 dropped Volta (sm_70/sm_72); cap V100s to cu128.
+                $cap = (& $smiExe --query-gpu=compute_cap --format=csv,noheader 2>$null |
+                    ForEach-Object { $_.Trim() } | Where-Object { $_ -match '^\d+\.\d+$' } |
+                    Sort-Object { [version]$_ } | Select-Object -First 1)
+                if ($cap -eq '7.0' -or $cap -eq '7.2') { return "cu128" }
+                return "cu130"
+            }
             if ($major -eq 12 -and $minor -ge 8) { return "cu128" }
             if ($major -eq 12 -and $minor -ge 6) { return "cu126" }
             if ($major -ge 12) { return "cu124" }
diff --git a/tests/sh/test_get_torch_index_url.sh b/tests/sh/test_get_torch_index_url.sh
index 23902097ef..988efc603f 100755
--- a/tests/sh/test_get_torch_index_url.sh
+++ b/tests/sh/test_get_torch_index_url.sh
@@ -90,6 +90,27 @@ MOCK
     echo "$_dir"
 }
 
+# Helper: mock nvidia-smi that also answers --query-gpu=compute_cap, so we can
+# exercise the Volta (sm_70/sm_72) cu130 -> cu128 cap. $1 = CUDA version,
+# $2 = compute_cap output (one cap per line; may be empty/malformed).
+make_mock_smi_caps() {
+    _dir=$(mktemp -d)
+    cat > "$_dir/nvidia-smi" <<MOCK
+#!/bin/sh
+case "\$*" in
+    *--query-gpu=compute_cap*) printf '%s\n' "$2" ;;
+    *)
+        case "\$1" in
+            -L) echo "GPU 0: NVIDIA Test GPU (UUID: GPU-fake-uuid)" ;;
+            *)  echo "| NVIDIA-SMI 590.00   Driver Version: 590.00   CUDA Version: $1   |" ;;
+        esac
+        ;;
+esac
+MOCK
+    chmod +x "$_dir/nvidia-smi"
+    echo "$_dir"
+}
+
 # Helper: create a mock amd-smi that prints a given ROCm version string
 # Supports both "amd-smi version" and "amd-smi list" subcommands so that
 # the GPU presence check (amd-smi list) also succeeds in tests.
@@ -435,6 +456,51 @@ assert_eq "url override path slash trimmed, query kept" "https://mirror.example.
 # 50) A #fragment ending in "/" is likewise preserved.
 _result=$(UNSLOTH_TORCH_INDEX_URL="https://mirror.example.com/whl/cu128#anchor/" run_func "none")
 assert_eq "url override preserves fragment slash" "https://mirror.example.com/whl/cu128#anchor/" "$_result"
+# --- Volta (sm_70/sm_72) capped to cu128 on CUDA 13 (cu130 dropped sm_70) ------
+# 51) CUDA 13.0 + Volta V100 (sm_70) -> cu128 (cu130 dropped sm_70)
+_dir=$(make_mock_smi_caps "13.0" "7.0")
+assert_eq "CUDA 13.0 + V100 (7.0) -> cu128" "https://download.pytorch.org/whl/cu128" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 52) CUDA 13.0 + Volta sm_72 -> cu128
+_dir=$(make_mock_smi_caps "13.0" "7.2")
+assert_eq "CUDA 13.0 + Volta (7.2) -> cu128" "https://download.pytorch.org/whl/cu128" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 53) CUDA 13.0 + Turing T4 (sm_75) -> cu130 (Turing is kept in cu130)
+_dir=$(make_mock_smi_caps "13.0" "7.5")
+assert_eq "CUDA 13.0 + T4 (7.5) -> cu130" "https://download.pytorch.org/whl/cu130" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 54) CUDA 13.0 + Ampere A100 (sm_80) -> cu130
+_dir=$(make_mock_smi_caps "13.0" "8.0")
+assert_eq "CUDA 13.0 + A100 (8.0) -> cu130" "https://download.pytorch.org/whl/cu130" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 55) CUDA 13.0 + Blackwell B200 (sm_100) -> cu130
+_dir=$(make_mock_smi_caps "13.0" "10.0")
+assert_eq "CUDA 13.0 + B200 (10.0) -> cu130" "https://download.pytorch.org/whl/cu130" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 56) CUDA 13.0 + mixed V100 + B200 -> cu128 (min cap is Volta)
+_dir=$(make_mock_smi_caps "13.0" "$(printf '10.0\n7.0')")
+assert_eq "CUDA 13.0 + mixed V100+B200 -> cu128" "https://download.pytorch.org/whl/cu128" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 57) CUDA 13.1 + V100 -> cu128 (any CUDA 13.x with Volta)
+_dir=$(make_mock_smi_caps "13.1" "7.0")
+assert_eq "CUDA 13.1 + V100 -> cu128" "https://download.pytorch.org/whl/cu128" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 58) CUDA 12.8 + V100 -> cu128 (12.x already ships sm_70; cap path not taken)
+_dir=$(make_mock_smi_caps "12.8" "7.0")
+assert_eq "CUDA 12.8 + V100 -> cu128" "https://download.pytorch.org/whl/cu128" "$(run_func "$_dir")"
+rm -rf "$_dir"
+
+# 59) CUDA 13.0 + empty compute_cap (query unsupported) -> cu130 (safe fallback)
+_dir=$(make_mock_smi_caps "13.0" "")
+assert_eq "CUDA 13.0 + empty cap -> cu130" "https://download.pytorch.org/whl/cu130" "$(run_func "$_dir")"
+rm -rf "$_dir"
 
 rm -f "$_FUNC_FILE"
 rm -rf "$_FAKE_SMI_DIR"