Unable to edit grub2 boot screen in centos 7

I have centos 7 gui installed on vmware workstation12 on my laptop.WhenI want to pause my splash screen while starting my centos 7 using the 'esc key' nothing happens and the system just boots up.I also see a entry for aci_memory_fail... entry during the boot process.help me fix the system.

You created this thread a few hours ago and I thought that I'd leave it for someone with greater knowledge than me. However, so far, no replies.

So here goes.

As far as I remember, the ESC key to interrupt Grub boot has been deprecated. I think that to interrupt boot on Grub2 you need to hold down a SHIFT key but I can't remember whether it's the left or right SHIFT key (or whether it even matters). Hold a SHIFT key for the whole boot process and see what happens.

Any member reading this and know whether I'm right or wrong please do let me and the OP know because I'm not sure either.

Hope that does help.