diff --git a/src/graph/rome_models.h b/src/graph/rome_models.h
index 20d08fe5b5..21b089c0b4 100755
--- a/src/graph/rome_models.h
+++ b/src/graph/rome_models.h
@@ -20,8 +20,8 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */
 
-#define MAX_ROME_GPUS 8
-#define MAX_ROME_NICS 2
+#define MAX_ROME_GPUS 16
+#define MAX_ROME_NICS 8
 
 struct rcclRomeModel {
   int nGpus;
@@ -235,6 +235,28 @@ static struct rcclRomeModel rome_model_46 = {
   .ringBase = "6 5 7 4 1 2 3 0|7 4 6 5 1 0 3 2",
 };
 
+static struct rcclRomeModel rome_model_48 = {
+  .nGpus = 8, .nCpus = 4, .nNics = 0, .nLinks = 3,
+  .gpuIds = { 0x4a000, 0x50000, 0xa000, 0xf000, 0xcb000, 0xd1000, 0x8a000, 0x90000, },
+  .nicIds = { },
+  .gpuNuma = { 0, 0, 1, 1, 2, 2, 3, 3, },
+  .nicNuma = { },
+  .connMatrix = { 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, },
+  .pattern = "20202020",
+  .ringBase = "0 1 2 3 4 5 6 7|7 6 5 4 3 2 1 0|0 1 2 3 4 5 6 7|7 6 5 4 3 2 1 0",
+};
+
+static struct rcclRomeModel rome_model_49 = {
+  .nGpus = 8, .nCpus = 4, .nNics = 4, .nLinks = 3,
+  .gpuIds = { 0x4a000, 0x50000, 0xa000, 0xf000, 0xcb000, 0xd1000, 0x8a000, 0x90000, },
+  .nicIds = { 0x45000, 0x13000, 0xc6000, 0x85000, },
+  .gpuNuma = { 0, 0, 1, 1, 2, 2, 3, 3, },
+  .nicNuma = { 0, 1, 2, 3, },
+  .connMatrix = { 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, },
+  .pattern = "21212121",
+  .ringBase = "N0 0 1 2 3 4 5 6 7 N3|N3 7 6 5 4 3 2 1 0 N0",
+};
+
 static struct rcclRomeModel romeTopoModels[] = {
   rome_model_22,
   rome_model_25,
@@ -254,4 +276,6 @@ static struct rcclRomeModel romeTopoModels[] = {
   rome_model_44,
   rome_model_45,
   rome_model_46,
+  rome_model_48,
+  rome_model_49,
 };
diff --git a/src/graph/search.cc b/src/graph/search.cc
index 097dcaaeb4..65eb5040f3 100644
--- a/src/graph/search.cc
+++ b/src/graph/search.cc
@@ -864,17 +864,6 @@ static ncclResult_t parseChordalRing(struct ncclTopoSystem* system, struct ncclT
   return ncclSuccess;
 }
 
-static bool getGpuNetCount(struct ncclTopoSystem* system, int id, int *g, int *n, int nnet, int *net_map) {
-  *g = 0; *n = 0;
-  int i;
-  if (ncclTopoIdToIndex(system, CPU, id, &i) == ncclInternalError) return false;
-  for (int j = 0; j < nnet; j++)
-    if (system->nodes[NET].nodes[net_map[j]].paths[CPU][i].count == 2) (*n)++;
-  for (int j = 0; j < system->nodes[GPU].count; j++)
-    if (system->nodes[GPU].nodes[j].paths[CPU][i].count == 2) (*g)++;
-  return true;
-}
-
 static ncclResult_t ncclGpuIdToIndex(struct ncclTopoSystem* system, int id, int* index) {
   *index = -1;
   for (int i=0; i<system->nodes[GPU].count; i++) {
@@ -893,12 +882,18 @@ static ncclResult_t parseRomeSystem(struct ncclTopoSystem* system, struct rcclRo
   romeTopo->nNics = 0;
   romeTopo->nLinks = 0;
   for (int i = 0; i < romeTopo->nGpus; i ++) {
-    int gpu, n;
+    int gpu, n, m, distance;
     NCCLCHECK(ncclGpuIdToIndex(system, i, &gpu));
     romeTopo->gpuIds[i] = system->nodes[GPU].nodes[gpu].id;
-    for (n = 0; n < romeTopo->nCpus; n++)
-      if (system->nodes[GPU].nodes[gpu].paths[CPU][n].count == 2) break;
-    if (n < romeTopo->nCpus) romeTopo->gpuNuma[i] = system->nodes[CPU].nodes[n].id;
+    m = 0;
+    distance = system->nodes[GPU].nodes[gpu].paths[CPU][m].count;
+    for (n = 1; n < romeTopo->nCpus; n++) {
+      if (system->nodes[GPU].nodes[gpu].paths[CPU][n].count < distance) {
+        distance = system->nodes[GPU].nodes[gpu].paths[CPU][n].count;
+        m = n;
+      }
+    }
+    if (m < romeTopo->nCpus) romeTopo->gpuNuma[i] = system->nodes[CPU].nodes[m].id;
 
     struct ncclTopoNode* node = system->nodes[GPU].nodes+gpu;
     if (node->paths[GPU] == NULL) continue;
@@ -936,24 +931,32 @@ static ncclResult_t parseRomeSystem(struct ncclTopoSystem* system, struct rcclRo
     }
   }
 
+  for (int i = 0; i < romeTopo->nNics; i ++) {
+    int net, n, m, distance;
+    NCCLCHECK(ncclTopoIdToIndex(system, NET, net_map[i], &net));
+    m = 0;
+    distance = system->nodes[NET].nodes[net].paths[CPU][m].count;
+    for (n = 0; n < romeTopo->nCpus; n++)
+      if (system->nodes[NET].nodes[net].paths[CPU][n].count < distance) {
+        distance = system->nodes[NET].nodes[net].paths[CPU][n].count;
+        m = n;
+      }
+    if (m < romeTopo->nCpus) romeTopo->nicNuma[i] = system->nodes[CPU].nodes[m].id;
+    else return ncclSuccess;
+  }
+
   // number of GPUs and NICs on each numa node is used as first screening pattern
   for (int i = 0; i < romeTopo->nCpus; i++) {
-    int g, n;
-    getGpuNetCount(system, i, &g, &n, romeTopo->nNics, net_map);
+    int g = 0, n = 0;
+    for (int j = 0; j < romeTopo->nGpus; j++)
+      if (romeTopo->gpuNuma[j] == i) g++;
+    for (int j = 0; j < romeTopo->nNics; j++)
+      if (romeTopo->nicNuma[j] == i) n++;
     pattern[i*2] = '0' + g;
     pattern[i*2+1] = '0' + n;
   }
   pattern[romeTopo->nCpus*2] = 0;
 
-  for (int i = 0; i < romeTopo->nNics; i ++) {
-    int net, n;
-    NCCLCHECK(ncclTopoIdToIndex(system, NET, net_map[i], &net));
-    for (n = 0; n < romeTopo->nCpus; n++)
-      if (system->nodes[NET].nodes[net].paths[CPU][n].count == 2) break;
-    if (n < romeTopo->nCpus) romeTopo->nicNuma[i] = system->nodes[CPU].nodes[n].id;
-    else return ncclSuccess;
-  }
-
   const char* romeModelFile = getenv("RCCL_DUMP_ROME_MODEL_FILE");
   if (romeModelFile) {
     INFO(NCCL_ENV, "RCCL_DUMP_ROME_MODEL_FILE set by environment to %s", romeModelFile);
diff --git a/tools/topo_expl/utils.cpp b/tools/topo_expl/utils.cpp
index e5bcf768fd..3d2a70dbbc 100644
--- a/tools/topo_expl/utils.cpp
+++ b/tools/topo_expl/utils.cpp
@@ -163,7 +163,7 @@ ncclResult_t initTransportsRank_1(struct ncclComm* comm, struct allGather1Data_t
   for (int i = 0; i < nranks; i++) {
     memcpy(comm->peerInfo+i, &allGather1Data[i].peerInfo, sizeof(struct ncclPeerInfo));
     if ((i != rank) && (comm->peerInfo[i].hostHash == myInfo->hostHash) && (comm->peerInfo[i].busId == myInfo->busId)) {
-      WARN("Duplicate GPU detected : rank %d and rank %d both on CUDA device %x", rank, i, myInfo->busId);
+      WARN("Duplicate GPU detected : rank %d and rank %d both on CUDA device %lx", rank, i, myInfo->busId);
       return ncclInvalidUsage;
     }
   }