diff --git a/src/modules/module_08900.c b/src/modules/module_08900.c
index 43a528158..06be00b6e 100644
--- a/src/modules/module_08900.c
+++ b/src/modules/module_08900.c
@@ -111,7 +111,7 @@ u64 module_extra_buffer_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE
   const u32 scrypt_N = (hashes->salts_buf[0].scrypt_N) ? hashes->salts_buf[0].scrypt_N : 1024;
   const u32 scrypt_r = (hashes->salts_buf[0].scrypt_r) ? hashes->salts_buf[0].scrypt_r : 1;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
   u32 tmto_start = 1;
   u32 tmto_stop  = 6;
@@ -224,7 +224,7 @@ u64 module_extra_tmp_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UN
     }
   }
 
-  const u64 tmp_size = (128 * scrypt_r * scrypt_p);
+  const u64 tmp_size = (u64)(128 * scrypt_r * scrypt_p);
 
   return tmp_size;
 }
@@ -242,13 +242,13 @@ char *module_jit_build_options (MAYBE_UNUSED const hashconfig_t *hashconfig, MAY
 
   const u64 extra_buffer_size = device_param->extra_buffer_size;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
-  const u64 size_scrypt = (128 * scrypt_r) * scrypt_N;
+  const u64 size_scrypt = (u64)(128 * scrypt_r * scrypt_N);
 
   const u64 scrypt_tmto_final = (kernel_power_max * size_scrypt) / extra_buffer_size;
 
-  const u64 tmp_size = (128 * scrypt_r) * scrypt_p;
+  const u64 tmp_size = (u64)(128 * scrypt_r * scrypt_p);
 
   char *jit_build_options = NULL;
 
diff --git a/src/modules/module_09300.c b/src/modules/module_09300.c
index a9ea1573c..70cbe6913 100644
--- a/src/modules/module_09300.c
+++ b/src/modules/module_09300.c
@@ -112,7 +112,7 @@ u64 module_extra_buffer_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE
   const u32 scrypt_r = 1;
   //const u32 scrypt_p = 1;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
   u32 tmto_start = 1;
   u32 tmto_stop  = 6;
@@ -231,13 +231,13 @@ char *module_jit_build_options (MAYBE_UNUSED const hashconfig_t *hashconfig, MAY
 
   const u64 extra_buffer_size = device_param->extra_buffer_size;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
-  const u64 size_scrypt = (128 * scrypt_r) * scrypt_N;
+  const u64 size_scrypt = (u64)(128 * scrypt_r * scrypt_N);
 
   const u64 scrypt_tmto_final = (kernel_power_max * size_scrypt) / extra_buffer_size;
 
-  const u64 tmp_size = (128 * scrypt_r) * scrypt_p;
+  const u64 tmp_size = (u64)(128 * scrypt_r * scrypt_p);
 
   char *jit_build_options = NULL;
 
diff --git a/src/modules/module_15700.c b/src/modules/module_15700.c
index 9f2700d65..2b814cc05 100644
--- a/src/modules/module_15700.c
+++ b/src/modules/module_15700.c
@@ -127,7 +127,7 @@ u64 module_extra_buffer_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE
   const u32 scrypt_r = (hashes->salts_buf[0].scrypt_r) ? hashes->salts_buf[0].scrypt_r : 8;
   //const u32 scrypt_p = (hashes->salts_buf[0].scrypt_p) ? hashes->salts_buf[0].scrypt_p : 1;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
   u32 tmto_start = 1;
   u32 tmto_stop  = 6;
@@ -240,7 +240,7 @@ u64 module_extra_tmp_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UN
     }
   }
 
-  const u64 tmp_size = (128 * scrypt_r * scrypt_p);
+  const u64 tmp_size = (u64)(128 * scrypt_r * scrypt_p);
 
   return tmp_size;
 }
@@ -269,13 +269,13 @@ char *module_jit_build_options (MAYBE_UNUSED const hashconfig_t *hashconfig, MAY
 
   const u64 extra_buffer_size = device_param->extra_buffer_size;
 
-  const u64 kernel_power_max = device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max;
+  const u64 kernel_power_max = (u64)(device_param->device_processors * hashconfig->kernel_threads_max * hashconfig->kernel_accel_max);
 
-  const u64 size_scrypt = (128 * scrypt_r) * scrypt_N;
+  const u64 size_scrypt = (u64)(128 * scrypt_r * scrypt_N);
 
   const u64 scrypt_tmto_final = (kernel_power_max * size_scrypt) / extra_buffer_size;
 
-  const u64 tmp_size = (128 * scrypt_r) * scrypt_p;
+  const u64 tmp_size = (u64)(128 * scrypt_r * scrypt_p);
 
   char *jit_build_options = NULL;