I hated not being able to undervolt in a7n8x by default, so i finally did that L11 bridge cutting. I cut the sidemost bridge that is beside the factory-cut bridge. This drops the default voltage from 1.65 to 1.25. First i tried with a sharp spike, but after rebooting there was no change. So, next try, i used a knife (actually the knife in a leatherman). Carefully pressing hard with the tip made a clean cut the width of the bridge. Now, when i started the computer, nothing happened. So i got worried. Flipped the on/off switch from the behind of the psu, and after the asus logo on the screen the bios told me that it had not been shutdowned correctly and is in safe mode, please go to bios to check everything. So i did, and found out that the selectable voltage range for vcore was now starting from 1.25 as i expected, but the upper high value was only 1.5V. I think this was a bit bad move from me since it would be good to have the possibility to use the original default voltage. I'll figure out later how to do that. Now, trying to use 1.5V with 166*12.5 default clockings did not work at all, i didn't get anything on screen and the same bios warning came on the next boot. So for now i just tried something like 166*9.5 and with that booted into windows just fine. Now i need to find out the fastest speed i can run with 1.5V. Too bad it won't run default speed with my new maximum voltage setting of 1.5V. I wonder if that is really because of the cpu or could the mobo have something to do with it... Anyway, now i just need to find the limits of my cpu.
Conclusion: Undervolting is possible with quite simple operation not requiring much skill even on motherboards that don't let you undervolt by default, However, it is important for the mobo to let you change the vcore at least upwards, because otherwise selecting different voltages is too hard work. And of course it voids the warranty for the cpu
Btw, anyone any good ideas how to make the upper limit for vcore a bit higher than 1.5V without rejoining the bridge?
asus a7n8x deluxe 2.0, barton 2800+, undervolting success
Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee
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I checked through my notes to see if I had tried any settings that might help you out. The fastest I have tried my Barton 2500+ at 1.5 vcore is 11*180=1980MHz. You tried 12.5*166=2075MHz, and that did not seem to work.
So, it seems likely that you could run 12*166=1992MHz since that is close to the 1980MHz that worked fine for me.
I did pass Prime95 without problems on 1980MHz.
So, it seems likely that you could run 12*166=1992MHz since that is close to the 1980MHz that worked fine for me.
I did pass Prime95 without problems on 1980MHz.
Hi lm, this is worth knowing as I have the same board, with a barton 2500. Except I'm more likely to overclock/over volt mine but anyway. It's possible the "Uber BIOS" would allow you the full voltage range on your modified CPU. One of the modifications is "CHIP Voltage Control selection choices now range from 1.6V - 1.9V." Usual warnings about risks of bios flashing, using modified bioses etc.
Seb
Seb
Hmm, the machine not really booting when turned on, was weird. Now i'm running at stock speed with voltage 1.5V. Maybe it had something to do with the fact that when it did that, the mobo was in front of my monitor, lying on a newspaper? After i assembled it back to the box, it has worked for couple days really well, and seems to be stable at stock speed with reduced voltage. I have not really cold booted this thing after that so i don't know yet for sure.
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Cold boot can often give stability problems when you are at the edge of your settings. Unfortunately you often get the same results when you have been in S3 mode. I don't think you had any problems running the board when it was on a newspaper.
I have had similar problems with startup problems when CPU is cold when my settings was close to what the CPU liked.
I have had similar problems with startup problems when CPU is cold when my settings was close to what the CPU liked.