diff --git a/generated/OpenBIOS.emitter.sha b/generated/OpenBIOS.emitter.sha
index 5f71563e..5b4ab659 100644
--- a/generated/OpenBIOS.emitter.sha
+++ b/generated/OpenBIOS.emitter.sha
@@ -1 +1 @@
-69641913e358f4c3128a93dadf5824c7929afeaf8df6c5b9a6cc645c0f43d0f5
+01cfc201a7c71e2555e5828c67aeaa29f295bf4ebfb4e182a3c606e2a4812857
diff --git a/recompiler/src/config_loader.cpp b/recompiler/src/config_loader.cpp
index ccf1e466..f6214cfc 100644
--- a/recompiler/src/config_loader.cpp
+++ b/recompiler/src/config_loader.cpp
@@ -618,16 +618,16 @@ static RuntimeConfig parse_runtime_block(const toml::value& cfg, const fs::path&
     // guest clock a fixed cost per instruction, and scale N charges 1/N of
     // it, so N times as much game code fits between two VBlanks while
     // VBlank, timers, CD, SPU and DMA keep hardware time. 1 = faithful;
-    // clamped to 1..64. guest_cycle_scale_gated: the scale applies only
+    // values outside 1..64 are rejected. guest_cycle_scale_gated: the scale applies only
     // while the mod gate is open (psx_mod_set_guest_cycle_scale_gate); see
     // guest_cycle_scale_gate below for the declarative RAM gate.
     if (cfg.contains("timing")) {
         const toml::value& tm = toml::find(cfg, "timing");
         if (tm.contains("guest_cycle_scale")) {
-            long long n = toml::find<long long>(tm, "guest_cycle_scale");
-            if (n < 1) n = 1;
-            if (n > 64) n = 64;
-            rt.guest_cycle_scale = (int)n;
+            const long long n = toml::find<long long>(tm, "guest_cycle_scale");
+            if (n < 1 || n > 64)
+                throw std::runtime_error("[timing] guest_cycle_scale must be 1..64");
+            rt.guest_cycle_scale = static_cast<int>(n);
         }
         if (tm.contains("guest_cycle_scale_gated"))
             rt.guest_cycle_scale_gated = toml::find<bool>(tm, "guest_cycle_scale_gated");
@@ -640,12 +640,22 @@ static RuntimeConfig parse_runtime_block(const toml::value& cfg, const fs::path&
             else preds.push_back(g);
             if (preds.size() > 8)
                 throw std::runtime_error("[timing] guest_cycle_scale_gate: at most 8 predicates");
+            // Range-check the signed TOML integer before narrowing, so an
+            // oversized or negative value cannot wrap into a valid one.
+            auto u32_field = [](const toml::value& pv, const char* key) -> uint32_t {
+                const long long v = toml::find<long long>(pv, key);
+                if (v < 0 || v > 0xFFFFFFFFLL)
+                    throw std::runtime_error(
+                        std::string("[timing] guest_cycle_scale_gate: ") + key +
+                        " must be 0..0xFFFFFFFF");
+                return static_cast<uint32_t>(v);
+            };
             for (const toml::value& pv : preds) {
                 RuntimeConfig::GuestCycleScaleGatePred p;
-                p.addr  = (uint32_t)toml::find<long long>(pv, "addr");
-                p.value = (uint32_t)toml::find<long long>(pv, "value");
-                if (pv.contains("size")) p.size = (uint32_t)toml::find<long long>(pv, "size");
-                if (pv.contains("mask")) p.mask = (uint32_t)toml::find<long long>(pv, "mask");
+                p.addr  = u32_field(pv, "addr");
+                p.value = u32_field(pv, "value");
+                if (pv.contains("size")) p.size = u32_field(pv, "size");
+                if (pv.contains("mask")) p.mask = u32_field(pv, "mask");
                 const uint32_t phys = p.addr & 0x1FFFFFFFu;
                 if ((p.size != 1 && p.size != 2 && p.size != 4) ||
                     (phys & (p.size - 1u)) != 0 || phys >= 0x00800000u)
diff --git a/recompiler/tests/video_enhancement_settings_test.cpp b/recompiler/tests/video_enhancement_settings_test.cpp
index 160ac3f1..21f7d88e 100644
--- a/recompiler/tests/video_enhancement_settings_test.cpp
+++ b/recompiler/tests/video_enhancement_settings_test.cpp
@@ -499,6 +499,29 @@ static void test_timing_gate() {
     try { (void)PSXRecompV4::load_game_config(p); } catch (const std::exception&) { rejected = true; }
     check(rejected, "timing: non-RAM gate address rejected");
     fs::remove(p);
+
+    /* Oversized and negative values must be rejected, not wrapped to 32 bits. */
+    const struct { const char* body; const char* what; } bad[] = {
+        { "guest_cycle_scale_gate = { addr = 0x100010000, value = 1 }", "oversized addr" },
+        { "guest_cycle_scale_gate = { addr = -4, value = 1 }", "negative addr" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = 0x100000001 }", "oversized value" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = -1 }", "negative value" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = 1, size = 0x100000004 }", "oversized size" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = 1, size = -4 }", "negative size" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = 1, mask = 0x1FFFFFFFF }", "oversized mask" },
+        { "guest_cycle_scale_gate = { addr = 0x80010000, value = 1, mask = -1 }", "negative mask" },
+        { "guest_cycle_scale = 0", "scale 0" },
+        { "guest_cycle_scale = 65", "scale 65" },
+        { "guest_cycle_scale = -8", "negative scale" },
+        { "guest_cycle_scale = 0x100000008", "oversized scale" },
+    };
+    for (const auto& b : bad) {
+        p = write_game_toml("ves_timing_range.toml", std::string("[timing]\n") + b.body + "\n");
+        rejected = false;
+        try { (void)PSXRecompV4::load_game_config(p); } catch (const std::exception&) { rejected = true; }
+        check(rejected, (std::string("timing: rejected ") + b.what).c_str());
+        fs::remove(p);
+    }
 }
 
 int main() {