diff --git a/src/transport/net.cc b/src/transport/net.cc
index e93d9e2748..7991754f65 100644
--- a/src/transport/net.cc
+++ b/src/transport/net.cc
@@ -248,7 +248,7 @@ end:
 extern bool useFineGrainVramPcie;
 
 NCCL_PARAM(NetGdrRead, "NET_GDR_READ", -2);
-NCCL_PARAM(NetGdrLevel, "NET_GDR_LEVEL", 0);
+NCCL_PARAM(NetGdrLevel, "NET_GDR_LEVEL", PATH_PHB);
 
 static ncclResult_t netGetGdrSupport(int dev, int read, int* useGdr) {
   *useGdr = 0;