Dual CPU expansion riser board for HP Z640. Operation check is good. It was working until just before, so I was using it without any problems. By inserting it with the same CPU and memory as the motherboard and booting, dual CPU operation can be easily achieved. Also, since the number of memory slots doubles to 8, a large amount of memory can be installed. The price of the CPU is not that high, so it is a very cost-effective upgrade. CPU cooler etc., of course, a complete set is included. No bent pins, all memory sockets OK. The overall condition is good, with almost no dirt, and the fans are also clean. It has been cleaned, and there is almost no grease residue. It will be shipped in a secure package.