CMDPHP: Poller[0] WARNING: SNMP Get Timeout for Host

[sumitdubey12345]

Getting this error in Cacti log,for C: Drive Space & CPU utilization in few hosts only. In rest hosts all graphs are populating.,
11/06/2013 12:40:44 PM - CMDPHP: Poller[0] WARNING: SNMP Get Timeout for Host:, and OID:'.1.3.6.1.2.1.1.3.0'
11/06/2013 12:40:42 PM - CMDPHP: Poller[0] Host DS[128] WARNING: Result from SNMP not valid. Partial Result: U.

[BSOD2600]

1) http://forums.cacti.net/viewtopic.php?f=3&t=11747
2) increase the snmp timeout for those devices.