diff --git a/projects/rccl/src/graph/connect.cc b/projects/rccl/src/graph/connect.cc
index 24b66f481c..7f52375ae8 100644
--- a/projects/rccl/src/graph/connect.cc
+++ b/projects/rccl/src/graph/connect.cc
@@ -240,7 +240,7 @@ int ncclMaxNchannels() {
   return maxNchannels;
 }
 
-ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePatterns, struct ncclTopoRanks** allTopoRanks, int* rings, int gcn, int nnets) {
+ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePatterns, struct ncclTopoRanks** allTopoRanks, int* rings, int nc) {
   // Gather data from all ranks
   int *ringRecv, *ringSend, *ringPrev, *ringNext, *treeToParent, *treeToChild0, *treeToChild1;
   int nranks = comm->nRanks;
@@ -272,13 +272,6 @@ ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePa
   memcpy(ringPrev+nChannels*nranks, ringPrev, nChannels*nranks*sizeof(int));
   memcpy(ringNext+nChannels*nranks, ringNext, nChannels*nranks*sizeof(int));
 
-  int nc = nChannels*2;
-  if (gcn == 908) nc = std::max(nc, 4);
-  if (comm->topo->nodes[GPU].count == comm->topo->nRanks && (comm->topo->type & RCCL_TOPO_CR8G)) nc = nChannels*4;
-  if (!nnets) nnets = comm->topo->nodes[NET].count;
-  if (nnets && (comm->topo->type & RCCL_TOPO_4P2H_ROME)) nc = (nnets > 3 ? 2 : 4)*nnets;
-  int end = std::min((int)ncclMaxNchannels(), std::max(nc, ncclMinNchannels()));
-
   // Duplication should be complete now
   nChannels = comm->nChannels = std::min(MAXCHANNELS,nChannels*2);
 
@@ -286,7 +279,7 @@ ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePa
   // We permit combining max, then min, to only use the first channels, then duplicate them.
   nChannels = comm->nChannels = std::min((int)ncclMaxNchannels(), nChannels);
   int c;
-  for (c=nChannels; c<end; c++) {
+  for (c=nChannels; c<std::min((int)ncclMaxNchannels(), std::max(nc, ncclMinNchannels())); c++) {
     memcpy(ringPrev+c*nranks, ringPrev+(c-nChannels)*nranks, nranks*sizeof(int));
     memcpy(ringNext+c*nranks, ringNext+(c-nChannels)*nranks, nranks*sizeof(int));
     memcpy(comm->channels+c, comm->channels+c-nChannels, sizeof(struct ncclChannel));
diff --git a/projects/rccl/src/include/graph.h b/projects/rccl/src/include/graph.h
index ac7fcbf992..893db11814 100644
--- a/projects/rccl/src/include/graph.h
+++ b/projects/rccl/src/include/graph.h
@@ -97,7 +97,7 @@ ncclResult_t ncclTopoPreset(struct ncclComm* comm,
     struct ncclTopoRanks* topoRanks);
 
 ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePatterns,
-    struct ncclTopoRanks** allTopoRanks, int* rings, int gcn, int nnets);
+    struct ncclTopoRanks** allTopoRanks, int* rings, int nc);
 
 ncclResult_t ncclTopoConnectCollNet(struct ncclComm* comm, struct ncclTopoGraph* collNetGraph, int rank);
 
diff --git a/projects/rccl/src/init.cc b/projects/rccl/src/init.cc
index 512114fd05..cefe38cad6 100644
--- a/projects/rccl/src/init.cc
+++ b/projects/rccl/src/init.cc
@@ -924,7 +924,7 @@ static ncclResult_t initTransportsRank(struct ncclComm* comm, ncclUniqueId* comm
     int cudaCompCap;
     int fullCudaCompCap;
     int nChannels;
-    int gcn;
+    int nc;
     struct ncclGraphInfo tree;
     struct ncclGraphInfo ring;
     struct ncclGraphInfo collNet;
@@ -935,10 +935,14 @@ static ncclResult_t initTransportsRank(struct ncclComm* comm, ncclUniqueId* comm
   int idx;
   NCCLCHECK(ncclTopoIdToIndex(comm->topo, GPU, myInfo->busId, &idx));
   allGather3Data[rank].cudaCompCap = comm->topo->nodes[GPU].nodes[idx].gpu.cudaCompCap;
-  allGather3Data[rank].gcn = comm->topo->nodes[GPU].nodes[idx].gpu.gcn;
-
   allGather3Data[rank].nChannels = comm->nChannels = treeGraph.nChannels = ringGraph.nChannels =
     std::min(treeGraph.nChannels, ringGraph.nChannels);
+  allGather3Data[rank].nc = comm->nChannels*2;
+  if (comm->topo->nodes[GPU].nodes[idx].gpu.gcn == 908) allGather3Data[rank].nc = std::max(allGather3Data[rank].nc, 4);
+  if (comm->topo->nodes[GPU].count == comm->topo->nRanks && (comm->topo->type & RCCL_TOPO_CR8G))
+    allGather3Data[rank].nc = comm->nChannels*4;
+  if (comm->topo->nodes[GPU].count != comm->topo->nRanks && comm->topo->nodes[NET].count && (comm->topo->type & RCCL_TOPO_4P2H_ROME))
+    allGather3Data[rank].nc = (comm->topo->nodes[NET].count > 3 ? 2 : 4)*comm->topo->nodes[NET].count;
   allGather3Data[rank].tree.pattern = treeGraph.pattern;
   allGather3Data[rank].tree.sameChannels = treeGraph.sameChannels;
   allGather3Data[rank].tree.speedIntra = treeGraph.speedIntra;
@@ -986,10 +990,10 @@ static ncclResult_t initTransportsRank(struct ncclComm* comm, ncclUniqueId* comm
   int nChannelsOrig = comm->nChannels;
   struct ncclTopoRanks** allTopoRanks;
   NCCLCHECK(ncclCalloc(&allTopoRanks, comm->nRanks));
-  int gcn = allGather3Data[0].gcn;
+  int nc = allGather3Data[0].nc;
   for (int i=0; i<nranks; i++) {
     allTopoRanks[i] = &allGather3Data[i].topoRanks;
-    gcn = std::min(allGather3Data[i].gcn, gcn);
+    nc = std::min(allGather3Data[i].nc, nc);
     // Make sure we align all ranks so that the tuning is consistent across ranks
     treeGraph.nChannels = ringGraph.nChannels = comm->nChannels = std::min(allGather3Data[i].nChannels, comm->nChannels);
     treeGraph.sameChannels = std::min(allGather3Data[i].tree.sameChannels, treeGraph.sameChannels);
@@ -1009,22 +1013,6 @@ static ncclResult_t initTransportsRank(struct ncclComm* comm, ncclUniqueId* comm
     collNetGraph.typeInter = std::min(allGather3Data[i].collNet.typeInter, collNetGraph.typeInter);
   }
 
-  // count NETs used by ring
-  int nNets = 0;
-  int nets[MAXCHANNELS*2];
-  // do not count NETs in case of single node, i.e comm->topo->nodes[GPU].count == comm->topo->nRanks
-  for (int i = 0; comm->topo->nodes[GPU].count != comm->topo->nRanks && i < ringGraph.nChannels; i++) {
-    for (int j = 0; j < 2; j++) {
-      int k;
-      for (k = 0; k < nNets; k++)
-        if (nets[k] == ringGraph.inter[i*2+j]) break;
-      if (k >= nNets) {
-        nets[nNets] = ringGraph.inter[i*2+j];
-        nNets++;
-      }
-    }
-  }
-
   if (comm->nChannels < nChannelsOrig) {
     // We started duplicating channels during Preset(), so we need to move the
     // duplicated channels since we have removed some.
@@ -1034,7 +1022,7 @@ static ncclResult_t initTransportsRank(struct ncclComm* comm, ncclUniqueId* comm
   int *rings;
   NCCLCHECK(ncclCalloc(&rings, nranks*MAXCHANNELS));
 
-  NCCLCHECK(ncclTopoPostset(comm, nodesFirstRank, nodesTreePatterns, allTopoRanks, rings, gcn, nNets));
+  NCCLCHECK(ncclTopoPostset(comm, nodesFirstRank, nodesTreePatterns, allTopoRanks, rings, nc));
   if (comm->nNodes > 1 &&
       ncclParamCollNetEnable() == 1 &&
       collNetSupport() && collNetGraph.nChannels) {
diff --git a/projects/rccl/tools/topo_expl/include/utils.h b/projects/rccl/tools/topo_expl/include/utils.h
index a111b8be29..62dd89d1cb 100644
--- a/projects/rccl/tools/topo_expl/include/utils.h
+++ b/projects/rccl/tools/topo_expl/include/utils.h
@@ -28,7 +28,7 @@ struct allGather3Data_t{
   int cudaCompCap;
   int fullCudaCompCap;
   int nChannels;
-  int gcn;
+  int nc;
   int alltoallDisable;
   struct ncclGraphInfo tree;
   struct ncclGraphInfo ring;
diff --git a/projects/rccl/tools/topo_expl/utils.cpp b/projects/rccl/tools/topo_expl/utils.cpp
index a18cd3e590..f6c0cee8e7 100644
--- a/projects/rccl/tools/topo_expl/utils.cpp
+++ b/projects/rccl/tools/topo_expl/utils.cpp
@@ -369,7 +369,7 @@ ncclResult_t initTransportsRank_1(struct ncclComm* comm, struct allGather1Data_t
     int cudaCompCap;
     int fullCudaCompCap;
     int nChannels;
-    int gcn;
+    int nc;
     struct ncclGraphInfo tree;
     struct ncclGraphInfo ring;
     struct ncclGraphInfo collNet;
@@ -381,10 +381,14 @@ ncclResult_t initTransportsRank_1(struct ncclComm* comm, struct allGather1Data_t
   int idx;
   NCCLCHECK(ncclTopoIdToIndex(comm->topo, GPU, myInfo->busId, &idx));
   allGather3Data[rank].cudaCompCap = comm->topo->nodes[GPU].nodes[idx].gpu.cudaCompCap;
-  allGather3Data[rank].gcn = comm->topo->nodes[GPU].nodes[idx].gpu.gcn;
-
   allGather3Data[rank].nChannels = comm->nChannels = treeGraph.nChannels = ringGraph.nChannels =
     std::min(treeGraph.nChannels, ringGraph.nChannels);
+  allGather3Data[rank].nc = comm->nChannels*2;
+  if (comm->topo->nodes[GPU].nodes[idx].gpu.gcn == 908) allGather3Data[rank].nc = std::max(allGather3Data[rank].nc, 4);
+  if (comm->topo->nodes[GPU].count == comm->topo->nRanks && (comm->topo->type & RCCL_TOPO_CR8G))
+    allGather3Data[rank].nc = comm->nChannels*4;
+  if (comm->topo->nodes[GPU].count != comm->topo->nRanks && comm->topo->nodes[NET].count && (comm->topo->type & RCCL_TOPO_4P2H_ROME))
+    allGather3Data[rank].nc = (comm->topo->nodes[NET].count > 3 ? 2 : 4)*comm->topo->nodes[NET].count;
   allGather3Data[rank].tree.pattern = treeGraph.pattern;
   allGather3Data[rank].tree.sameChannels = treeGraph.sameChannels;
   allGather3Data[rank].tree.speedIntra = treeGraph.speedIntra;
@@ -578,10 +582,10 @@ ncclResult_t initTransportsRank_3(struct ncclComm* comm, struct allGather3Data_t
   int nChannelsOrig = comm->nChannels;
   struct ncclTopoRanks** allTopoRanks;
   NCCLCHECK(ncclCalloc(&allTopoRanks, comm->nRanks));
-  int gcn = allGather3Data[0].gcn;
+  int nc = allGather3Data[0].nc;
   for (int i=0; i<nranks; i++) {
     allTopoRanks[i] = &allGather3Data[i].topoRanks;
-    gcn = std::min(allGather3Data[i].gcn, gcn);
+    nc = std::min(allGather3Data[i].nc, nc);
     // Make sure we align all ranks so that the tuning is consistent across ranks
     treeGraph.nChannels = ringGraph.nChannels = comm->nChannels = std::min(allGather3Data[i].nChannels, comm->nChannels);
     treeGraph.sameChannels = std::min(allGather3Data[i].tree.sameChannels, treeGraph.sameChannels);
@@ -601,22 +605,6 @@ ncclResult_t initTransportsRank_3(struct ncclComm* comm, struct allGather3Data_t
     collNetGraph.typeInter = std::min(allGather3Data[i].collNet.typeInter, collNetGraph.typeInter);
   }
 
-  // count NETs used by ring
-  int nNets = 0;
-  int nets[MAXCHANNELS*2];
-  // do not count NETs in case of single node, i.e comm->topo->nodes[GPU].count == comm->topo->nRanks
-  for (int i = 0; comm->topo->nodes[GPU].count != comm->topo->nRanks && i < ringGraph.nChannels; i++) {
-    for (int j = 0; j < 2; j++) {
-      int k;
-      for (k = 0; k < nNets; k++)
-        if (nets[k] == ringGraph.inter[i*2+j]) break;
-      if (k >= nNets) {
-        nets[nNets] = ringGraph.inter[i*2+j];
-        nNets++;
-      }
-    }
-  }
-
   if (comm->nChannels < nChannelsOrig) {
     // We started duplicating channels during Preset(), so we need to move the
     // duplicated channels since we have removed some.
@@ -626,7 +614,7 @@ ncclResult_t initTransportsRank_3(struct ncclComm* comm, struct allGather3Data_t
   int *rings;
   NCCLCHECK(ncclCalloc(&rings, nranks*MAXCHANNELS));
 
-  NCCLCHECK(ncclTopoPostset(comm, nodesFirstRank, nodesTreePatterns, allTopoRanks, rings, gcn, nNets));
+  NCCLCHECK(ncclTopoPostset(comm, nodesFirstRank, nodesTreePatterns, allTopoRanks, rings, nc));
   if (comm->nNodes > 1 &&
       ncclParamCollNetEnable() == 1 &&
       collNetSupport() && collNetGraph.nChannels) {