Currently Intel's cheapest dual-core CPU is the Pentium D 820 which ships for $241. The Pentium D 805 should even be cheaper.
According to a short report published by the Asian web-site, the new Pentium D 805 would be mainly promoted among system makers in conjunction with inexpensive Intel 945GZ core-logic, which is only expected to be available in the beginning of next year, which may indicate that Intel’s 2.66GHz dual-core chip is not something, which will be available shortly.Competitor AMD also prepares cheaper dual-core CPUs but those are unlikely to be priced less than $300. More details at X-bit Labs