diff --git a/common.go b/common.go
index 5b2c666..276d176 100644
--- a/common.go
+++ b/common.go
@@ -7,6 +7,7 @@ package tls
 import (
 	"container/list"
 	"crypto"
+	"crypto/internal/cipherhw"
 	"crypto/rand"
 	"crypto/sha512"
 	"crypto/x509"
@@ -919,11 +920,46 @@ func defaultCipherSuites() []uint16 {
 }
 
 func initDefaultCipherSuites() {
+	var topCipherSuites []uint16
+	if cipherhw.AESGCMSupport() {
+		// If AES-GCM hardware is provided then prioritise AES-GCM
+		// cipher suites.
+		topCipherSuites = []uint16{
+			TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+			TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+			TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+			TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
+			TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
+			TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
+		}
+	} else {
+		// Without AES-GCM hardware, we put the ChaCha20-Poly1305
+		// cipher suites first.
+		topCipherSuites = []uint16{
+			TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
+			TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
+			TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+			TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+			TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+			TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
+		}
+	}
+
 	varDefaultCipherSuites = make([]uint16, 0, len(cipherSuites))
+	for _, topCipher := range topCipherSuites {
+		varDefaultCipherSuites = append(varDefaultCipherSuites, topCipher)
+	}
+
+NextCipherSuite:
 	for _, suite := range cipherSuites {
 		if suite.flags&suiteDefaultOff != 0 {
 			continue
 		}
+		for _, existing := range varDefaultCipherSuites {
+			if existing == suite.id {
+				continue NextCipherSuite
+			}
+		}
 		varDefaultCipherSuites = append(varDefaultCipherSuites, suite.id)
 	}
 }