Glad to you radaja & ezaleina, Thanks zodden for your info, I just notice that CPU VTT is relate to MCH reference (if you set MCH ref. to non auto)
And now I can boot up success to window at VTT 1.28 and MCH ref around 0.64 ( but show in ET6 0.90) .Still not test a stable yet. But this is
first time I can boot up to window with below 1.60 VTT, I'll post the test later.