Newegg offers the refurbished Dell OptiPlex GX390 Intel Sandy Bridge Core i3 3.1GHz Desktop PC (no monitor) for $179.99. This $30 mail-in rebate drops it to $149.99. With free shipping, that's $150 under list and the lowest total price we could find. It features an Intel Core i3-2100 3.1GHz Sandy Bridge dual-core processor, 4GB RAM, 250GB hard drive, and Windows 7 Professional 64-Bit. Deal ends May 31.
A 90-day warranty applies, but it's unclear who backs it.