
Answer: You can tell the difference from the part number that is engraved in to the circuit board of the Amd Fire Pro Graphic cards also amount of soldiered memory chip and the memory chip manufacture part numbers. the link below takes you to our website where you can find all the graphic cards for the a1481 and you can see all the part numbers, good luck
Here is the list of all AMD FirePro Graphic Card Gpu & Direct Link To each For more details
D300 AMD FirePro Card A ( without ssd )
Parts Number : 820-3627-A
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d300-2gb-820-3627-a-video-graphic-card-a/
D300 AMD FirePro Card B ( With ssd )
Parts Number : 820-3630-A
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d300-2gb-820-3630-a-video-graphic-card-b/
D500 AMD FirePro Card A ( without ssd )
Parts Number : 820-3532-A
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d500-3gb-820-3532-a-video-graphic-card-a/
D500 AMD FirePro Card B ( With ssd )
Parts Number : 820-3533-07
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d500-3gb-820-3533-07-video-graphic-card-b/
D700 AMD FirePro Card A ( Without ssd )
Parts Number : 820-3532-07 , 661-7532
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d700-6gb-820-3532-a-video-graphic-card-a/
D700 AMD FirePro Card B ( With ssd )
Parts Number : 661-7547, 820-3532-A
Link to Purchase : https://tekdep.com/product/apple-2013-mac-pro-a1481-amd-firepro-d700-6gb-820-3532-a-video-graphic-card-b/
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