Try removing the Dell supplied module, that'll tell you if the Dell BIOS is very restrictive on what it'll accept or if it is downclocking due to mixing different types.

Yeah.. the Dell BIOS isn't going to support the XMP settings.

Without the XMP settings available, you are stuck with whatever the JDEC SPD settings are programmed to on the modules.

Sounds to me like the JDEC SPD settings don't include a 2400 setting and that is why it is dropping back to 2133.

You might be able to flash your RAM to support the higher settings but in doing that you also run the risk of bricking the RAM... Maybe test out on an old stick first?

https://www.overclock.net/forum/18051-memory/ … dr4-eeprom.html

http://www.softnology.biz/

Use CPU-Z to look at the SPD settings programmed on the G.Skill RAM. I am betting that there is no 2400 SPD setting.

BushLin wrote:

Try removing the Dell supplied module, that'll tell you if the Dell BIOS is very restrictive on what it'll accept or if it is downclocking due to mixing different types.

The Dell module was never in there in the first place, that's what I theorized would happen. I've got both G.Skill sticks in there (there's only two slots on the motherboard) for a total of 16GB.

cyclone3d wrote:

Yeah.. the Dell BIOS isn't going to support the XMP settings. […]
Show full quote

Yeah.. the Dell BIOS isn't going to support the XMP settings.

Without the XMP settings available, you are stuck with whatever the JDEC SPD settings are programmed to on the modules.

Sounds to me like the JDEC SPD settings don't include a 2400 setting and that is why it is dropping back to 2133.

You might be able to flash your RAM to support the higher settings but in doing that you also run the risk of bricking the RAM... Maybe test out on an old stick first?

https://www.overclock.net/forum/18051-memory/ … dr4-eeprom.html

http://www.softnology.biz/

Use CPU-Z to look at the SPD settings programmed on the G.Skill RAM. I am betting that there is no 2400 SPD setting.

The JDEC settings on this only go from 2036MHz, to 2132MHz. The XMP allows it to go to 3000MHz. I don't want to risk bricking the RAM, but I will see about getting it up to 2400MHz with one of the default sticks before I go any further.

[EDIT]

So, sticking in the 2400MHz stick isn't going to work. It does exactly what I thought it would. I also can't apply any changes I make with Thaiphoon- I'm assuming I'd have to buy some version of it to actually do anything but read the current timings/speeds of the RAM. Even if I could apply the changes, I don't know enough about RAM itself to figure that out. So I guess I'm stuck at 2134MHz. My only choice from here is to figure out how much performance I'll be losing, it seems. Nothing else I can really do.

Thaiphoon will allow changes to the RAM, but not to RAM with write-protected areas. Among other brands, Hynix write-protects the areas Thaiphoon would need to access to change the SPD options, and there's apparently little you can do to change this from read only to read/write. My RAM uses Hynix chips.

The Dell BIOS is of course locked in such a way as to prevent me from manually bringing the RAM to 2400MHz. I looked it up, and I am apparently losing quite a bit of performance with this reduction in RAM speed. I figured a potential way to get this RAM to where I needed it to be was to try to find a modified BIOS for the system, but all I found was this: https://www.bios-mods.com/forum/Thread-REQUES … ron-5675-unlock

The potential of the x370 chipset on this motherboard is noted, but one of the people trying to grab a valid "BIOS dump," managed to overvolt his BIOS chip and it ostensibly died. After the 6th of this month (June), all progress on modding the BIOS stopped. At this point, I'm assuming that option is no longer relevant. I did find references to software that allowed you to temporarily change RAM speed on a tom's hardware forum post, but it was ancient and the last update it got was to support DDR3 and 1st gen Core i7s, so it's unlikely it would support a modern AM4/DDR4 system.

I am unsure of why the people modding the BIOS couldn't use the BIOS file given by Dell, and needed a hardware read of the chip itself. There's probably something there that I don't understand (assembly-level gibberish), but it doesn't make much sense to me.