diff --git a/network/3com/snmp/mode/cpu.pm b/network/3com/snmp/mode/cpu.pm
index 8804ac90b..1f38a6da6 100644
--- a/network/3com/snmp/mode/cpu.pm
+++ b/network/3com/snmp/mode/cpu.pm
@@ -187,7 +187,7 @@ sub manage_selection {
     my $results = $options{snmp}->get_table(oid => $oid_hwCpuEntry, nothing_quit => 1);
     $self->{cpu} = {};
     foreach my $oid (keys %{$results}) {
-        next if ($oid !~ /^$mapping->{hwMemSize}->{oid}\.(.*)/);
+        next if ($oid !~ /^$mapping->{hwCpuCostRatePer5Min}->{oid}\.(.*)/);
         my $instance = $1;
         my $result = $options{snmp}->map_instance(mapping => $mapping, results => $results, instance => $instance);