Precision 7550 change memory speed via nvram change

I have a precision 7550 laptop from dell that i got as a replacement for an older model. it came with ram specified as 3200mhz but will only run it as 2933mhz as thats the default max ram speed. can anyone either tell me how to use setup_var_3 or just mod the nvram from the fptw bios dump so it will run the ram at 3200mhz at 22-22-22-52-74 timings? i would really prefer the instructions on how to change it myself but i understand if its too much work to explain it. i have tried it already using setup body ifr and grub with setup_var_3 but it doesn’t seem to be able to write the correct value.

the link for the bios file is here: