Question RAM noob needs a simple answer

Chris8282

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I bought some Corsair Vengeance LPX memory rated at 2666 Mhz CL15. It runs at 2133 Mhz CL15 in my PC because that is the JEDEC specs for the module. My motherboard does not support XMP and the BIOS does not allow altering RAM. My motherboard supports 2666 Mhz.

I'm going a bit nuts getting contradictory, complex information I don't fully understand. Please, please help!

So my question is, does there exist a purchaseable RAM with JEDEC specs that is better than 2400 Mhz CL17 or 2666 Mhz CL19 which is all I can find and my Google Fu tells me has worse absolute latency. Where and how do I pick these out?

Or, more simply, is there a way for me to get any modules that perform better at JEDEC spec (without XMP or BIOS) or 2666 Mhz and below?
 
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Karadjgne

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Default speed of DDR4 is 2133MHz. Xmp is nothing more than a profile, not governed by jadec standards for timings. Many of the early B350/A320 motherboards only supported 2133MHz regardless of xmp, ram speeds, jadec etc, so had no options for any other than default ddr4 2133MHz in bios.

That may have been changed by later bios updates with included Agesa microcode.

2666MHz ram will have access to all the jadec tables if that speed or any lower, since those already exist as a table even upto 2933MHz exists as that is a default cpu memory controller speed, but if there are no options in bios to select a table or speed, the bios has no options but to accept only the default speed of the ddr4, 2133MHz.
 

Chris8282

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My motherboard is an HP Edoras that came with an HP Omen Obelisk 875-0014. Sorry I forgot to mention that, I did in another thread but Ilm getting exhausted, its been a long couple of days researching. My previous memory was 2666 Mhz CL19 so I bought 2666 Mhz CL15 thinking it would work, but what I am wondering is if the RAM I bought isn't actually 2666 Mhz without XMP. It is the Corsair Vengeance LPX. I researched HyperX Fury 2666 Mhz and its Plug n Play but it seems it defaults to 2400 Mhz CL17.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://support.hp.com/us-en/document/c06124984&ved=2ahUKEwis556fo8v6AhVKZTABHWBWCfAQFnoECAgQAQ&usg=AOvVaw3WLy0uPVNw7Pfi36WRHIGt

This the MB

https://www.newegg.com/corsair-32gb-288-pin-ddr4-sdram/p/N82E16820233853?tpk=1

This is the RAM.

So if I bought a true JEDEC RAM at 26666 Mhz it would try to work at the lowest JEDEC spec for 2666 Mhz that my MB supports, hopefully CL17? So the true issue is that the RAM itself is not true JEDEC 2666 Mhz? How do I find what a RAMs true JEDEC is since HyperX Fury is the only ones with proper documentation I found.
 
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I bought some Corsair Vengeance LPX memory rated at 2666 Mhz CL15. It runs at 2133 Mhz CL15 in my PC because that is the JEDEC specs for the module. My motherboard does not support XMP and the BIOS does not allow altering RAM. My motherboard supports 2666 Mhz.

I'm going a bit nuts getting contradictory, complex information I don't fully understand. Please, please help!

So my question is, does there exist a purchaseable RAM with JEDEC specs that is better than 2400 Mhz CL17 or 2666 Mhz CL19 which is all I can find and my Google Fu tells me has worse absolute latency. Where and how do I pick these out?

Or, more simply, is there a way for me to get any modules that perform better at JEDEC spec (without XMP or BIOS) or 2666 Mhz and below?
You might want to see if there is a bios update for your pc and then try this new ram again.

https://support.hp.com/us-en/drivers/selfservice/omen-by-hp-obelisk-desktop-pc-875-0000a/23302709/model/23574497
 

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