diff --git a/ggml/src/ggml-vulkan/vulkan-shaders/dequant_funcs_cm2.comp b/ggml/src/ggml-vulkan/vulkan-shaders/dequant_funcs_cm2.comp
index 109a6b864..974efd3f9 100644
--- a/ggml/src/ggml-vulkan/vulkan-shaders/dequant_funcs_cm2.comp
+++ b/ggml/src/ggml-vulkan/vulkan-shaders/dequant_funcs_cm2.comp
@@ -368,23 +368,25 @@ layout(buffer_reference, std430, buffer_reference_align = 2) buffer decodeBufIQ2
 
 float16_t dequantFuncIQ2_S(const in decodeBufIQ2_S bl, const in uint blockCoords[2], const in uint coordInBlock[2])
 {
-    const float16_t d = bl.block.d;
-    const uint idx = coordInBlock[1];
+    uint idx = coordInBlock[1];
+    uint lsb = idx & 1;
+    idx /= 2;
 
-    const uint ib32 = (idx & 0xE0) >> 5; // 0..7
-    const uint ib8 = (idx & 0xF8) >> 3;  // 0..31
-    const uint qhshift = 2 * (ib8 % 4);
+    const uint ib8 = (idx % 128) / 4; // 0..31
+    const uint ib32 = ib8 / 4;        // 0..7
 
-    const uint scale = (bl.block.scales[ib32] >> ((idx & 0x10) >> 4)) & 0xf;
+    const uint scale = (bl.block.scales[ib32] >> (2 * (ib8 & 2))) & 0xf;
     const uint qs = bl.block.qs[ib8];
     const uint qh = bl.block.qh[ib32];
-    const uint sign = bl.block.qs[QUANT_K / 8 + ib8];
+    const uint qhshift = 2 * (ib8 % 4);
+    const uint sign = bl.block.qs[QUANT_K / 8 + ib8] >> (2 * (idx % 4));
 
-    const float16_t dscale = bl.block.d * 0.25hf * (0.5hf + float16_t(scale));
-    const uint8_t g = unpack8(iq2s_grid[qs | ((qh << (8 - qhshift)) & 0x300)][(idx & 4) >> 2])[idx & 3];
-
-    float16_t ret = dscale * float16_t(g) * ((sign & (1 << (idx & 7))) != 0 ? -1.0hf : 1.0hf);
-    return ret;
+    const float d = float(bl.block.d);
+    const float db = d * 0.25 * (0.5 + scale);
+    const i8vec2 sign01 = i8vec2(1 - (2 & i8vec2(int8_t(sign << 1), int8_t(sign))));
+    const uint16_t grid = unpack16(iq2s_grid[qs | ((qh << (8 - qhshift)) & 0x300)][(idx & 2) >> 1])[idx & 1];
+    const vec2 v = db * vec2(sign01) * vec2(unpack8(grid));
+    return float16_t(v[lsb]);
 }
 #endif
 
@@ -399,25 +401,28 @@ layout(buffer_reference, std430, buffer_reference_align = 2) buffer decodeBufIQ3
 
 float16_t dequantFuncIQ3_XXS(const in decodeBufIQ3_XXS bl, const in uint blockCoords[2], const in uint coordInBlock[2])
 {
-    decodeBufIQ3_XXS_packed16 bl16 = decodeBufIQ3_XXS_packed16(bl);
-    const float16_t d = bl.block.d;
-    const uint idx = coordInBlock[1];
+    uint idx = coordInBlock[1];
+    uint lsb = idx & 1;
+    idx /= 2;
 
-    const uint ib32 = (idx & 0xE0) >> 5; // 0..7
-    const uint ib4 = (idx & 0xFC) >> 4;  // 0..63
-    const uint is16 = QUANT_K / 8 + 2 * ib32; // index in packed16
+    const uint iqs = (idx % 128) / 2;           // 0..63
+    const uint is = QUANT_K / 4 + 4 * (iqs / 8); // 8 values
 
-    const uint8_t qs = bl.block.qs[ib4];
-    const uint signscale = pack32(u16vec2(bl16.block.qs[is16], bl16.block.qs[is16+1]));
-
-    const float16_t dscale = bl.block.d * 0.5hf * (0.5hf + float16_t(signscale >> 28));
-    uint sign = bitfieldExtract(signscale, 7 * int(ib4 & 3), 7);
-    sign |= bitCount(sign) << 7;
-
-    const uint8_t g = unpack8(iq3xxs_grid[qs])[idx & 3];
-
-    float16_t ret = dscale * float16_t(g) * ((sign & (1 << (idx & 7))) != 0 ? -1.0hf : 1.0hf);
-    return ret;
+    const float d = float(bl.block.d);
+    const uint qs = bl.block.qs[iqs];
+    const uint signs = pack32(u8vec4(
+        bl.block.qs[is+0],
+        bl.block.qs[is+1],
+        bl.block.qs[is+2],
+        bl.block.qs[is+3]
+    ));
+    const float db = d * 0.5 * (0.5 + (signs >> 28));
+    const uint32_t sign7 = bitfieldExtract(signs, 7 * (int(iqs / 2) % 4), 7);
+    const uint sign = (sign7 | (bitCount(sign7) << 7)) >> (2 * (idx % 4));
+    const i8vec2 sign01 = i8vec2(1 - (2 & i8vec2(int8_t(sign << 1), int8_t(sign))));
+    const uint grid = iq3xxs_grid[qs] >> (16 * (idx & 1));
+    const vec2 v = db * vec2(sign01) * vec2(unpack8(grid).xy);
+    return float16_t(v[lsb]);
 }
 #endif
 
@@ -428,26 +433,24 @@ layout(buffer_reference, std430, buffer_reference_align = 2) buffer decodeBufIQ3
 
 float16_t dequantFuncIQ3_S(const in decodeBufIQ3_S bl, const in uint blockCoords[2], const in uint coordInBlock[2])
 {
-    const float16_t d = bl.block.d;
-    const uint idx = coordInBlock[1];
+    uint idx = coordInBlock[1];
+    uint lsb = idx & 1;
+    idx /= 2;
 
-    const uint iqs = (idx & 0xFC) >> 2;  // 0..63
-    const uint iqh = (idx & 0xE0) >> 5;  // 0..7
-    const uint qhbit = iqs & 7;
-    const uint isgn = (idx & 0xF8) >> 3; // 0..31
-    const uint is = (idx & 0xC0) >> 6;   // 0..3
-
-    const uint8_t scale = (bl.block.scales[is] >> ((idx & 0x20) >> 3)) & uint8_t(0xF);
-    const float16_t dscale = d * (1.0hf + float16_t(2 * scale));
+    const uint iqs = (idx % 128) / 2;           // 0..63
+    const uint iqh = iqs / 8;
 
+    const float d = float(bl.block.d);
     const uint qs = bl.block.qs[iqs];
-    const uint qh = (bl.block.qh[iqh] << (8 - qhbit)) & 0x100;
-    const uint8_t sign = bl.block.signs[isgn];
+    const uint qh = bl.block.qh[iqh];
+    const int8_t sign = int8_t(bl.block.signs[iqs / 2] >> (2 * (idx % 4)));
+    const uint scale = bl.block.scales[iqs / 16];
+    const i8vec2 sign01 = i8vec2(1 - (2 & i8vec2(sign << 1, sign)));
+    const float db = d * (1 + 2 * ((scale >> (4 * (iqh & 1))) & 0xf));
+    const uint32_t grid = iq3s_grid[qs | ((qh << (8 - (iqs % 8))) & 256)] >> (16 * (idx % 2));
+    const vec2 v = db * vec2(sign01) * vec2(unpack8(grid).xy);
 
-    const uint g = unpack8(iq3s_grid[qs | qh])[idx & 3];
-    float16_t ret = dscale * float16_t(g) * ((sign & (1 << (idx & 7))) != 0 ? -1.0hf : 1.0hf);
-
-    return ret;
+    return float16_t(v[lsb]);
 }
 #endif