diff --git a/libcpuid/cpuid_main.c b/libcpuid/cpuid_main.c
index c638f09..a32805a 100644
--- a/libcpuid/cpuid_main.c
+++ b/libcpuid/cpuid_main.c
@@ -452,6 +452,7 @@ const char* cpu_feature_str(cpu_feature_t feature)
 		{ CPU_FEATURE_3DNOW, "3dnow" },
 		{ CPU_FEATURE_3DNOWEXT, "3dnowext" },
 		{ CPU_FEATURE_NX, "nx" },
+		{ CPU_FEATURE_FXSR_OPT, "fxsr_opt" },
 		{ CPU_FEATURE_RDTSCP, "rdtscp" },
 		{ CPU_FEATURE_LM, "lm" },
 		{ CPU_FEATURE_LAHF_LM, "lahf_lm" },
diff --git a/libcpuid/libcpuid.h b/libcpuid/libcpuid.h
index d31b3ac..e6dfa7d 100644
--- a/libcpuid/libcpuid.h
+++ b/libcpuid/libcpuid.h
@@ -281,6 +281,7 @@ enum _cpu_feature_t {
 	CPU_FEATURE_3DNOW,	/*!< AMD 3DNow! instructions supported */
 	CPU_FEATURE_3DNOWEXT,	/*!< AMD 3DNow! extended instructions supported */
 	CPU_FEATURE_NX,		/*!< No-execute bit supported */
+	CPU_FEATURE_FXSR_OPT,	/*!< FFXSR: FXSAVE and FXRSTOR optimizations */
 	CPU_FEATURE_RDTSCP,	/*!< RDTSCP instruction supported (AMD-only) */
 	CPU_FEATURE_LM,		/*!< Long mode (x86_64/EM64T) supported */
 	CPU_FEATURE_LAHF_LM,	/*!< LAHF/SAHF supported in 64-bit mode */
diff --git a/libcpuid/recog_amd.c b/libcpuid/recog_amd.c
index 1609be9..d1b9fb5 100644
--- a/libcpuid/recog_amd.c
+++ b/libcpuid/recog_amd.c
@@ -159,6 +159,7 @@ static void load_amd_features(struct cpu_raw_data_t* raw, struct cpu_id_t* data)
 	const struct feature_map_t matchtable_edx81[] = {
 		{ 20, CPU_FEATURE_NX },
 		{ 22, CPU_FEATURE_MMXEXT },
+		{ 25, CPU_FEATURE_FXSR_OPT },
 		{ 27, CPU_FEATURE_RDTSCP },
 		{ 30, CPU_FEATURE_3DNOWEXT },
 		{ 31, CPU_FEATURE_3DNOW },