Hello, When replacing the motherboard on an E521 he damaged the processor when putting it back on. The current one is an AMD Sempron sda3400iaa3cn. All I want to do is purchase one to replace it that will go on the the new motherboard compatibable part numbers: UW457 CT107 HK980
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If the pins aren't broken, you should be able to fix it by bending them back. If you still want a new cpu, Ewiz has the amd 5000+ 2.6 Ghz 65 nm cpu for $40. It should work in your dell board, and the heatsink should be adequate.