Underclocking Memory

[joelp]

Hello Everyone. I have just received all my parts for my PC build.

 

Mainboard - Gigabyte GA-Z790 Gaming X AX

CPU - Intel i7 14700KF

Memory - Corsair Vengeance (2 x 16GB, 7200 MHz, DDR5)

 

My Problem:

The memory kit runs on 7200 MHz (34-44-44-96) and a whopping 1.45 volts. Surely the Motherboard will throttle the frequency automatically. But setting the XMP profile scares me, taking into account that the maximum supply voltage for the memory controller is around 1.15 volts. Is it possible to set the frequency to 5600MHz (what the CPU supports) and maybe get the CAS delay down a little bit at a reasonable voltage without stressing the CPU too much?

 

Thank you all for your input.

[AndreiArgeanu]

You can easily turn the frequency down if you choose so, and I think CAS latency comes down as well automatically, but if it doesn't or you want to get it down further you can tune it manually, but that requires some trial and error, and long memory test to ensure stability. You can do all of this in the bios.

 

However the automatic XMP profiles in the bios should be safe and shouldn't cause any problems. If they did, then they wouldn't be there, or the would be at a lower frequency by default.

[RONOTHAN##]

Think you have a few misconceptions about what's going on here and the apparent danger levels (or more accurately, lack-thereof). 

 

First off, the memory voltage on DDR5 doesn't touch the CPU, it stays on the actual memory chips. There's other voltages for powering the memory controller and that the data bus transmits on, and those are handled mostly independently of the XMP voltage. Even for those voltages though, 1.45V is still within safe range and not really anything to be concerned about. 

 

Second, 5600MT/s is only there for RMA purposes. In reality, every single LGA 1700 CPU will be able to run frequencies above this, and almost all 14th gen chips should be fine running DDR5 7200. 

 

 

Yes, it's possible to run tighter timings at DDR5 5600 with something like 1.3V, but why would you? You paid extra for the higher speed memory kit, you might as well actually use it. 

 

2 minutes ago, AndreiArgeanu said:

and I think CAS latency comes down as well automatically

Most boards I've used will turn the timings up automatically as you increase frequency, though as you decrease frequency they'll keep using whatever the XMP/JEDEC timings are (whatever is tighter), since there is plenty of memory that will not do low timings no matter what frequency you're at, so scaling it linearly downwards would lead to instability. 

[joelp]

1 hour ago, AndreiArgeanu said:

You can easily turn the frequency down if you choose so, and I think CAS latency comes down as well automatically, but if it doesn't or you want to get it down further you can tune it manually, but that requires some trial and error, and long memory test to ensure stability. You can do all of this in the bios.

 

However the automatic XMP profiles in the bios should be safe and shouldn't cause any problems. If they did, then they wouldn't be there, or the would be at a lower frequency by default.

Thanks for your input. It‘s much appreciated!

[joelp]

5 hours ago, RONOTHAN## said:

Think you have a few misconceptions about what's going on here and the apparent danger levels (or more accurately, lack-thereof). 

 

First off, the memory voltage on DDR5 doesn't touch the CPU, it stays on the actual memory chips. There's other voltages for powering the memory controller and that the data bus transmits on, and those are handled mostly independently of the XMP voltage. Even for those voltages though, 1.45V is still within safe range and not really anything to be concerned about. 

 

Second, 5600MT/s is only there for RMA purposes. In reality, every single LGA 1700 CPU will be able to run frequencies above this, and almost all 14th gen chips should be fine running DDR5 7200. 

 

 

Yes, it's possible to run tighter timings at DDR5 5600 with something like 1.3V, but why would you? You paid extra for the higher speed memory kit, you might as well actually use it. 

 

Most boards I've used will turn the timings up automatically as you increase frequency, though as you decrease frequency they'll keep using whatever the XMP/JEDEC timings are (whatever is tighter), since there is plenty of memory that will not do low timings no matter what frequency you're at, so scaling it linearly downwards would lead to instability. 

Thanks for your input and clarifying so much! Running XMP seems like a safe bet in my situation then. I might get back to you if I run in any problems.