If your bios is 1708, would try updating to the very latest to 2501 as from version 1708 to version 2103 are added support for newer cpus. Perhaps yours will work with a later Bios.
Thanks boju
i have done all that the guide says. I have put my old phenom II 3.4ghz in and it boots i have also checked the bios and it has the latest for the 9590 cpu but not for the part number that is on the cpu box.
Ok no worries, go by the model (FX9590) and not the part number. Part number is the factory ID when it was made. Your motherboard should support it, check your BIOS version again, it needs to be version 1708 or higher.
If your bios is 1708, would try updating to the very latest to 2501 as from version 1708 to version 2103 are added support for newer cpus. Perhaps yours will work with a later Bios.