I believe they are inductors, part of a switch-mode power supply to reduce the voltage of incoming power to the level required by the cores (AFAIK ~1V).
The definitely are inductors (being labeled "Lxx" on PCB is a sure tell-tale sign), and the small 48ish pin packages near them are most likely SMPS controllers. Seems bit crazy that there are total of 18 of them, but I suppose that's what you gotta do when you are pushing possibly hundreds of amps of current.
Makes the normal buck converter arrangement too. Controller, inductor, diode. The GPU will be taking like half a volt so things are definitely going to be getting toasty.
Those big two-legged components look like caps to me though.