Which model can I test LPDDR4x 4266Mbps device?

I am interested in your VIM3 and VIM4 models.
I would like to test the LPDDR4x(VDDQ=0.6V) 4266MHz full speed DRAM.
Please tell me the maximum DRAM clock speed supported by VIM3 and VIM4 models.
If I replace with my LPDDR4x 4266Mbps device, can I test 4266Mbps?