The new AMD processors BE-2300 and BE-2350 which have similar speed to 3600+ and 4000+ respectively, are now out on newegg
Newegg.com - AMD Athlon X2 BE-2350 Brisbane 2.1GHz 2 x 512KB L2 Cache Socket AM2 Processor - Retail
Newegg.com - AMD Athlon X2 BE-2300 Brisbane 1.9GHz 2 x 512KB L2 Cache Socket AM2 Processor - Retail
Those new processors consume only 45W only compared to the older Brisbane which consume 65W
Newegg.com - AMD Athlon X2 BE-2350 Brisbane 2.1GHz 2 x 512KB L2 Cache Socket AM2 Processor - Retail
Newegg.com - AMD Athlon X2 BE-2300 Brisbane 1.9GHz 2 x 512KB L2 Cache Socket AM2 Processor - Retail
Those new processors consume only 45W only compared to the older Brisbane which consume 65W