diff --git a/configure.ac b/configure.ac
index 61b47e7..2664707 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([ccminer], [1.6.1])
+AC_INIT([ccminer], [1.6.2-git])
 
 AC_PREREQ([2.59c])
 AC_CANONICAL_SYSTEM
diff --git a/cpuminer-config.h b/cpuminer-config.h
index 1264f97..ca8c8cc 100644
--- a/cpuminer-config.h
+++ b/cpuminer-config.h
@@ -159,7 +159,7 @@
 #define PACKAGE_NAME "ccminer"
 
 /* Define to the full name and version of this package. */
-#define PACKAGE_STRING "ccminer 1.6.1"
+#define PACKAGE_STRING "ccminer 1.6.2-git"
 
 /* Define to the one symbol short name of this package. */
 #define PACKAGE_TARNAME "ccminer"
@@ -168,7 +168,7 @@
 #define PACKAGE_URL "http://github.com/tpruvot/ccminer"
 
 /* Define to the version of this package. */
-#define PACKAGE_VERSION "1.6.1"
+#define PACKAGE_VERSION "1.6.2-git"
 
 /* If using the C implementation of alloca, define if you know the
    direction of stack growth for your system; otherwise it will be
@@ -191,7 +191,7 @@
 /* undef USE_XOP */
 
 /* Version number of package */
-#define VERSION "1.6.1"
+#define VERSION "1.6.2-git"
 
 /* Define curl_free() as free() if our version of curl lacks curl_free. */
 /* #undef curl_free */
diff --git a/quark/cuda_skein512.cu b/quark/cuda_skein512.cu
index 669ec4a..472341e 100644
--- a/quark/cuda_skein512.cu
+++ b/quark/cuda_skein512.cu
@@ -4,7 +4,7 @@
 
 #include "cuda_helper.h"
 
-static __constant__ uint64_t c_PaddedMessage80[16]; // padded message (80 bytes + padding)
+static __constant__ uint64_t c_PaddedMessage80[20]; // padded message (80 bytes + 72 bytes midstate + align)
 
 // Take a look at: https://www.schneier.com/skein1.3.pdf
 
@@ -303,6 +303,47 @@ uint64_t skein_rotl64(const uint64_t x, const int offset)
 		TFBIG_MIX8(p[6], p[1], p[0], p[7], p[2], p[5], p[4], p[3],  8, 35, 56, 22); \
 	}
 
+/* uint64_t midstate for skein 80 */
+
+#define TFBIG_ADDKEY_PRE(w0, w1, w2, w3, w4, w5, w6, w7, k, t, s) { \
+		w0 = (w0 + SKBI(k, s, 0)); \
+		w1 = (w1 + SKBI(k, s, 1)); \
+		w2 = (w2 + SKBI(k, s, 2)); \
+		w3 = (w3 + SKBI(k, s, 3)); \
+		w4 = (w4 + SKBI(k, s, 4)); \
+		w5 = (w5 + SKBI(k, s, 5) + SKBT(t, s, 0)); \
+		w6 = (w6 + SKBI(k, s, 6) + SKBT(t, s, 1)); \
+		w7 = (w7 + SKBI(k, s, 7) + (s)); \
+	}
+
+#define TFBIG_MIX_PRE(x0, x1, rc) { \
+		x0 = x0 + x1; \
+		x1 = ROTL64(x1, rc) ^ x0; \
+	}
+
+#define TFBIG_MIX8_PRE(w0, w1, w2, w3, w4, w5, w6, w7, rc0, rc1, rc2, rc3) { \
+		TFBIG_MIX_PRE(w0, w1, rc0); \
+		TFBIG_MIX_PRE(w2, w3, rc1); \
+		TFBIG_MIX_PRE(w4, w5, rc2); \
+		TFBIG_MIX_PRE(w6, w7, rc3); \
+	}
+
+#define TFBIG_4e_PRE(s) { \
+		TFBIG_ADDKEY_PRE(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], h, t, s); \
+		TFBIG_MIX8_PRE(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 46, 36, 19, 37); \
+		TFBIG_MIX8_PRE(p[2], p[1], p[4], p[7], p[6], p[5], p[0], p[3], 33, 27, 14, 42); \
+		TFBIG_MIX8_PRE(p[4], p[1], p[6], p[3], p[0], p[5], p[2], p[7], 17, 49, 36, 39); \
+		TFBIG_MIX8_PRE(p[6], p[1], p[0], p[7], p[2], p[5], p[4], p[3], 44,  9, 54, 56); \
+	}
+
+#define TFBIG_4o_PRE(s) { \
+		TFBIG_ADDKEY_PRE(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], h, t, s); \
+		TFBIG_MIX8_PRE(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 39, 30, 34, 24); \
+		TFBIG_MIX8_PRE(p[2], p[1], p[4], p[7], p[6], p[5], p[0], p[3], 13, 50, 10, 17); \
+		TFBIG_MIX8_PRE(p[4], p[1], p[6], p[3], p[0], p[5], p[2], p[7], 25, 29, 39, 43); \
+		TFBIG_MIX8_PRE(p[6], p[1], p[0], p[7], p[2], p[5], p[4], p[3],  8, 35, 56, 22); \
+	}
+
 /* uint2 variant for SM3.2+ */
 
 #define TFBIG_KINIT_UI2(k0, k1, k2, k3, k4, k5, k6, k7, k8, t0, t1, t2) { \
@@ -560,69 +601,30 @@ void skein512_gpu_hash_80(uint32_t threads, uint32_t startNounce, uint64_t *outp
 		uint2 h0, h1, h2, h3, h4, h5, h6, h7, h8;
 		uint2 t0, t1, t2;
 
-		// Init
-		h0 = vectorize(0x4903ADFF749C51CEull);
-		h1 = vectorize(0x0D95DE399746DF03ull);
-		h2 = vectorize(0x8FD1934127C79BCEull);
-		h3 = vectorize(0x9A255629FF352CB1ull);
-		h4 = vectorize(0x5DB62599DF6CA7B0ull);
-		h5 = vectorize(0xEABE394CA9D5C3F4ull);
-		h6 = vectorize(0x991112C71A75B523ull);
-		h7 = vectorize(0xAE18A40B660FCC33ull);
+		h0 = vectorize(c_PaddedMessage80[10]);
+		h1 = vectorize(c_PaddedMessage80[11]);
+		h2 = vectorize(c_PaddedMessage80[12]);
+		h3 = vectorize(c_PaddedMessage80[13]);
+		h4 = vectorize(c_PaddedMessage80[14]);
+		h5 = vectorize(c_PaddedMessage80[15]);
+		h6 = vectorize(c_PaddedMessage80[16]);
+		h7 = vectorize(c_PaddedMessage80[17]);
 
-		// 1st step -> etype = 0xE0, ptr = 64, bcount = 0, extra = 0
-		t0 = vectorize(64); // ptr
-		//t1 = vectorize(0xE0ull << 55); // etype
-		t1 = vectorize(0x7000000000000000ull);
-		TFBIG_KINIT_UI2(h0, h1, h2, h3, h4, h5, h6, h7, h8, t0, t1, t2);
-
-		uint2 p[8];
-		#pragma unroll 8
-		for (int i = 0; i<8; i++)
-			p[i] = vectorize(c_PaddedMessage80[i]);
-
-		TFBIG_4e_UI2(0);
-		TFBIG_4o_UI2(1);
-		TFBIG_4e_UI2(2);
-		TFBIG_4o_UI2(3);
-		TFBIG_4e_UI2(4);
-		TFBIG_4o_UI2(5);
-		TFBIG_4e_UI2(6);
-		TFBIG_4o_UI2(7);
-		TFBIG_4e_UI2(8);
-		TFBIG_4o_UI2(9);
-		TFBIG_4e_UI2(10);
-		TFBIG_4o_UI2(11);
-		TFBIG_4e_UI2(12);
-		TFBIG_4o_UI2(13);
-		TFBIG_4e_UI2(14);
-		TFBIG_4o_UI2(15);
-		TFBIG_4e_UI2(16);
-		TFBIG_4o_UI2(17);
-		TFBIG_ADDKEY_UI2(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], h, t, 18);
-
-		h0 = vectorize(c_PaddedMessage80[0]) ^ p[0];
-		h1 = vectorize(c_PaddedMessage80[1]) ^ p[1];
-		h2 = vectorize(c_PaddedMessage80[2]) ^ p[2];
-		h3 = vectorize(c_PaddedMessage80[3]) ^ p[3];
-		h4 = vectorize(c_PaddedMessage80[4]) ^ p[4];
-		h5 = vectorize(c_PaddedMessage80[5]) ^ p[5];
-		h6 = vectorize(c_PaddedMessage80[6]) ^ p[6];
-		h7 = vectorize(c_PaddedMessage80[7]) ^ p[7];
+		t2 = vectorize(c_PaddedMessage80[18]);
 
 		uint32_t nonce = swap ? cuda_swab32(startNounce + thread) : startNounce + thread;
-		uint2 nounce2 = make_uint2(_LOWORD(c_PaddedMessage80[9]), nonce);
+		uint2 nonce2 = make_uint2(_LOWORD(c_PaddedMessage80[9]), nonce);
 
-		// skein_big_close -> etype = 0x160, ptr = 16, bcount = 1, extra = 16
+		uint2 p[8];
 		p[0] = vectorize(c_PaddedMessage80[8]);
-		p[1] = nounce2;
+		p[1] = nonce2;
 
 		#pragma unroll
 		for (int i = 2; i < 8; i++)
 			p[i] = vectorize(0ull);
 
-		t0 = vectorize(0x50ull); // SPH_T64(bcount << 6) + (sph_u64)(extra);
-		t1 = vectorize(0xB000000000000000ull); // (bcount >> 58) + ((sph_u64)(etype) << 55);
+		t0 = vectorize(0x50ull);
+		t1 = vectorize(0xB000000000000000ull);
 		TFBIG_KINIT_UI2(h0, h1, h2, h3, h4, h5, h6, h7, h8, t0, t1, t2);
 		TFBIG_4e_UI2(0);
 		TFBIG_4o_UI2(1);
@@ -646,7 +648,7 @@ void skein512_gpu_hash_80(uint32_t threads, uint32_t startNounce, uint64_t *outp
 
 		uint64_t *outpHash = &output64[thread * 8];
 		outpHash[0] = c_PaddedMessage80[8] ^ devectorize(p[0]);
-		outpHash[1] = devectorize(nounce2 ^ p[1]);
+		outpHash[1] = devectorize(nonce2 ^ p[1]);
 		#pragma unroll
 		for(int i=2; i<8; i++)
 			outpHash[i] = devectorize(p[i]);
@@ -888,12 +890,71 @@ void quark_skein512_cpu_hash_64(int thr_id, uint32_t threads, uint32_t startNoun
 
 /* skein / skein2 */
 
+__host__
+static void skein512_precalc_80(uint64_t* message)
+{
+	uint64_t h0, h1, h2, h3, h4, h5, h6, h7, h8;
+	uint64_t t0, t1, t2;
+
+	h0 = 0x4903ADFF749C51CEull;
+	h1 = 0x0D95DE399746DF03ull;
+	h2 = 0x8FD1934127C79BCEull;
+	h3 = 0x9A255629FF352CB1ull;
+	h4 = 0x5DB62599DF6CA7B0ull;
+	h5 = 0xEABE394CA9D5C3F4ull;
+	h6 = 0x991112C71A75B523ull;
+	h7 = 0xAE18A40B660FCC33ull;
+	h8 = h0 ^ h1 ^ h2 ^ h3 ^ h4 ^ h5 ^ h6 ^ h7 ^ SPH_C64(0x1BD11BDAA9FC1A22);
+
+	t0 = 64; // ptr
+	t1 = 0x7000000000000000ull;
+	t2 = 0x7000000000000040ull;
+
+	uint64_t p[8];
+	for (int i = 0; i<8; i++)
+		p[i] = message[i];
+
+	TFBIG_4e_PRE(0);
+	TFBIG_4o_PRE(1);
+	TFBIG_4e_PRE(2);
+	TFBIG_4o_PRE(3);
+	TFBIG_4e_PRE(4);
+	TFBIG_4o_PRE(5);
+	TFBIG_4e_PRE(6);
+	TFBIG_4o_PRE(7);
+	TFBIG_4e_PRE(8);
+	TFBIG_4o_PRE(9);
+	TFBIG_4e_PRE(10);
+	TFBIG_4o_PRE(11);
+	TFBIG_4e_PRE(12);
+	TFBIG_4o_PRE(13);
+	TFBIG_4e_PRE(14);
+	TFBIG_4o_PRE(15);
+	TFBIG_4e_PRE(16);
+	TFBIG_4o_PRE(17);
+	TFBIG_ADDKEY_PRE(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], h, t, 18);
+
+	message[10] = message[0] ^ p[0];
+	message[11] = message[1] ^ p[1];
+	message[12] = message[2] ^ p[2];
+	message[13] = message[3] ^ p[3];
+	message[14] = message[4] ^ p[4];
+	message[15] = message[5] ^ p[5];
+	message[16] = message[6] ^ p[6];
+	message[17] = message[7] ^ p[7];
+
+	message[18] = t2;
+}
+
 __host__
 void skein512_cpu_setBlock_80(void *pdata)
 {
-	cudaMemcpyToSymbol(c_PaddedMessage80, pdata, 80, 0, cudaMemcpyHostToDevice);
+	uint64_t message[20];
+	memcpy(&message[0], pdata, 80);
+	skein512_precalc_80(message);
+	cudaMemcpyToSymbol(c_PaddedMessage80, message, sizeof(message), 0, cudaMemcpyHostToDevice);
 
-	CUDA_SAFE_CALL(cudaStreamSynchronize(NULL));
+	CUDA_SAFE_CALL(cudaGetLastError());
 }
 
 __host__