I search service manual for XFX RADEON HD 7770 or circuit diagram. NOT USER MANUAL!!!
I believe that AMD doesn't supply circuit diagrams but possibly Service Manual (For Reference GPU card ) but no harm in asking by opening a Online AMD SERVICE REQUEST (Official AMD SUPPORT) from here: https://www.amd.com/en/support/contact-email-form
XFX wouldn't provide you with a Service Manual?
They are the ones that manufactured the GPU card.
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