boot grub2

sorry if this answer has been already answered, I was trying to google.
Here is the problem, I have opensuse tumbleweed, first I tried to install uefi (with having only one partition /boot/efi as sda1, but it was saying missing os)
Now it is working for me, i reinstalled to grub legacy, but it is terribly slow the grub load.
Welcome to GRUB takes 10 seconds, then black screen 20 seconds, then boot list is unusable, after that, it is booting very swiftly.

Disk /dev/sda: 111.8 GiB, 120034123776 bytes, 234441648 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 20645C42-8C11-43D8-BBEC-A8A91F18975E

Device        Start       End   Sectors  Size Type
/dev/sda1      2048    530431    528384  258M BIOS boot
/dev/sda2    530432   5830655   5300224  2.5G Linux swap
/dev/sda3   5830656  66654207  60823552   29G Linux filesystem
/dev/sda4  66654208 234440703 167786496   80G Linux filesystem

and my grub partitions:

localhost:~ # df -h | grep -i grub
/dev/sda3        30G  5.5G   24G  19% /boot/grub2/i386-pc
/dev/sda3        30G  5.5G   24G  19% /boot/grub2/x86_64-efi

Any hint where to start debugging please ?
I checked /var/log/boot.log, does not show anything related IMO