Dabadger84



So I somehow missed this post until just now and actually answered him in PM, but I'm going to repost it here because the reasons I think it's done is actually a pretty important one, depending on what kind of undervolt you're running:
 
It depends on the type of undervolt you're going for.  If you're going for super-low voltage with semi-stock clocks, the -60 part makes sure the entire curve is "under" what you're going to set clocks wise.
If you're aiming for something more "up there" like 2040MHz @ 1000mV on a 3090 for example, you don't need to do that part I don't think, as the entire curve for the 3090 FTW3 is under 2040MHz.

Basically the negative offset at the start is to make sure your "curve" is flat AFTER the point you set, to minimize the weird behavior.  I still get Afterburner occasionally letting the clock go 15MHz over what I set, which when I'm really pushing it, can result in a crash, since, if 15MHz higher was stable, I'd be running it 15MHz higher. lol

For my card as an example, I have to do a slight negative offset to do 2100MHz @ 1025mV (one of my two very stable settings) because the top of my curve goes to 2115MHz otherwise, and that can cause it to step over what I have set.  If I'm testing my higher setting, which is going to be somewhere between 2145 @ 1050mV & 2160MHz @ 1068mV (basically stock voltage but with a nice OC), I don't need the negative offset, because the clock I'm setting is higher than the highest line of the curve.
 
- Hope that helps anyone that has questions about that, as that's my understanding of why it's done/when it should be done and when it shouldn't.

I am a bit confused here and maybe something is not right, I am not sure. 
 
So I have been doing some testing in the 2 main titles I play. iRacing and Assetto Corsa Competizione on triple 1440p monitors running @ 7680x1440p and wanted to compare to my 3080 XC3.  
The 3080 is getting similar FPS as the 3090 with the same in game settings in iRacing and actually the 3080 is getting slightly better at some instances. Also in iRacing there is a meter to measure GPU frame times and the 3080 is actually running a bit more headroom as well running the same exact settings. 
 
In ACC with the same settings the 3090 is doing about 10FPS more vs the 3080. Is there room for me to improve on this with the 3090 once I get my new PSU? I am running your undervolt recommendation and power limit @ 100% currently on the 3090. The 3080 is running on stock settings. 

daveargentino

Dabadger84



So I somehow missed this post until just now and actually answered him in PM, but I'm going to repost it here because the reasons I think it's done is actually a pretty important one, depending on what kind of undervolt you're running:
 
It depends on the type of undervolt you're going for.  If you're going for super-low voltage with semi-stock clocks, the -60 part makes sure the entire curve is "under" what you're going to set clocks wise.
If you're aiming for something more "up there" like 2040MHz @ 1000mV on a 3090 for example, you don't need to do that part I don't think, as the entire curve for the 3090 FTW3 is under 2040MHz.

Basically the negative offset at the start is to make sure your "curve" is flat AFTER the point you set, to minimize the weird behavior.  I still get Afterburner occasionally letting the clock go 15MHz over what I set, which when I'm really pushing it, can result in a crash, since, if 15MHz higher was stable, I'd be running it 15MHz higher. lol

For my card as an example, I have to do a slight negative offset to do 2100MHz @ 1025mV (one of my two very stable settings) because the top of my curve goes to 2115MHz otherwise, and that can cause it to step over what I have set.  If I'm testing my higher setting, which is going to be somewhere between 2145 @ 1050mV & 2160MHz @ 1068mV (basically stock voltage but with a nice OC), I don't need the negative offset, because the clock I'm setting is higher than the highest line of the curve.
 
- Hope that helps anyone that has questions about that, as that's my understanding of why it's done/when it should be done and when it shouldn't.

I am a bit confused here and maybe something is not right, I am not sure. 
 
So I have been doing some testing in the 2 main titles I play. iRacing and Assetto Corsa Competizione on triple 1440p monitors running @ 7680x1440p and wanted to compare to my 3080 XC3.  
The 3080 is getting similar FPS as the 3090 with the same in game settings in iRacing and actually the 3080 is getting slightly better at some instances. Also in iRacing there is a meter to measure GPU frame times and the 3080 is actually running a bit more headroom as well running the same exact settings. 
 
In ACC with the same settings the 3090 is doing about 10FPS more vs the 3080. Is there room for me to improve on this with the 3090 once I get my new PSU? I am running your undervolt recommendation and power limit @ 100% currently on the 3090. The 3080 is running on stock settings. 

The undervolt/OC is just a starting point, feel free to play with it.  You can either go for nice clocks with good temps & power draw (which the 2040MHz @ 1025mV should give you if it's a 3090 non-Kingpin), or you can try to push it to the max.  The ideal behind that would be having a constant stock or near-stock voltage (unless you're hitting power limit, then it will throttle of course) with higher, flatter/more sustained clocks.
 
I don't play racing titles at all (except NFS & I haven't played those in a while) so I can't comment too much on how performance is in those titles.  I think the new PSU will probably give the 3090 better, cleaner power, and might indeed boost your performance with it though.  Hope so!