Overclock.net - An Overclocking Community - View Single Post - ROG Crosshair VII overclocking thread
View Single Post
post #820 of (permalink) Old 05-08-2018, 01:17 AM - Thread Starter
New to Overclock.net
elmor's Avatar
Join Date: Mar 2014
Posts: 864
Rep: 353 (Unique: 157)
Quote: Originally Posted by gupsterg View Post
PSA C7H Peeps

SB voltage on [Auto] IMO seems crazy excessive on UEFI 0601.

My build was uneventful up til posting and using UEFI.

I flashbacked UEFI 0601 prior to 1st powerup, removed power from board, then did clear CMOS. I then powered up, went to do screen shot of Main page and CPU page, rig rebooted . I tried again and it rebooted . I stopped taking screen shots via F12.

Checked UEFI and found SB voltage readout at 1.094V, applied a DMM to ProbeIt point and it read back as 1.115V . A manual setting of 1V yielded in 1.064/5V, same as what my C6H would be when set at 1.05V or [Auto] in UEFI and when measured at ProbeIt point.

SOC was read lower in UEFI than Ryzen Gen 1, using DMM on ProbeIt it was ~0.800V. Near enough 0.075V-0.125V lower than several Ryzen Gen 1 CPUs I used on C6H. So SOC [Auto] was as it should be.

RAM [Auto] was 1.202V on ProbeIt point, all good.

PLL [Auto] I never measured, but 1.8V manually set was read back via DMM on ProbeIt point as 1.8V steady as it was on my C6H.
Quote: Originally Posted by crakej View Post
My SB was identical to yours! Elmor or Stilt did mention something about voltage the other day when I reported my PLL voltage as low - seemed to think it was most likely a readout error. Maybe one of them can clear this up for us. Do your other voltages report as you would expect?

I have my DMM - will have a test in a while and report back.

There's a small issue on the first batches of boards where the droop from the VRM output to the SB input is a relatively large (~50mV). The read point for both software and ProbeIt is at the VRM output, so it will read higher (before droop). Ie the VRM is outputting ~50mV higher than what the SB is actually getting. Not pretty but it shouldn't be a cause for concern. If you set it to ~1.0V in BIOS to get a 1.05V readout, technically you're undervolting the rail.
elmor is offline