Time for dynamic is in microseconds, not ms.
diff --git a/driver-opencl.c b/driver-opencl.c
index 8bd876b..eec6ce7 100644
--- a/driver-opencl.c
+++ b/driver-opencl.c
@@ -1504,7 +1504,7 @@ static int64_t opencl_scanhash(struct thr_info *thr, struct work *work,
clFinish(clState->commandQueue);
/* Windows' timer resolution is only 15ms so oversample 5x */
- if (gpu->dynamic && (++gpu->intervals * dynamic_us) > 75) {
+ if (gpu->dynamic && (++gpu->intervals * dynamic_us) > 70000) {
struct timeval tv_gpuend;
double gpu_us;