I need a little help with my rig

I just built my computer and I was wondering if I could receive a little help with overclocking it and whats best recommended for my system. Any help would be greatly appreciated. Stock (1.8), the CPU idles at 43C but just with a tiny overclock up to 2.0 it idles at 52C. Here are the specs:


-AMD Opteron 165 Denmark 1.8GHz 2 x 1MB L2 Cache Socket 939 Dual Core Processor (stock heatsink with thermal grease)
-OCZ GameXStream OCZ700GXSSLI ATX12V 700W Power Supply 100 - 240 V
-2X - (SLI) - EVGA 256-P2-N615-TX GeForce 7600GT 256MB 128-bit GDDR3 PCI Express x16 Video Card
-G.SKILL 2GB (2 x 1GB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Dual Channel Kit Desktop Memory
-ABIT AN8 32X Motherboard - ATX - nForce4 SLI - Socket 939
-Antec Nine Hundred case