I too am affected by slow console when GRUB_TERMINAL_MODE is set to gfxmode in GRUB 2.04 and earlier versions. I believe this problem is not resolution-specific; but suffers under VBE mode.
I can also verify that I don't have this issue with syslinux (which uses VGA modes).
System spec:
CPU: Core i7 990x | Motherboard: Asus Rampage 3 Extreme | Graphics: EVGA GTX760
I too am affected by slow console when GRUB_TERMINAL_MODE is set to gfxmode in GRUB 2.04 and earlier versions. I believe this problem is not resolution- specific; but suffers under VBE mode.
I can also verify that I don't have this issue with syslinux (which uses VGA modes).
System spec:
CPU: Core i7 990x | Motherboard: Asus Rampage 3 Extreme | Graphics: EVGA GTX760