The entire GIF loop makes a point of how faster RAM means faster gaming, and four memory modules are displayed throughout.
Now, the next image is immediately afterwards, and purportedly demonstrates the difference faster RAM makes to games (specifically Marvel's Spider-Man). A 31% FPS increase by moving from 3000 MT/s RAM to 6000 MT/s RAM.
Same Core i9-13900K / RTX4090 combo, going from 2x 16GB 3000MT/s CL18 DDR4 RAM to 2x 16GB 6000MT/s CL38 DDR5
Leaving aside the bandwidth increase from DDR4 to DDR5 (which means each test used a different motherboard), note the number of RAM modules.
I've been building PCs for a looooong time, and I've forgotten more than I remember.
But very specifically, I've been working primarily with ITX motherboards that have two RAM slots.
I like my pretty RAM, and all the photos in Corsair (and other ads) show all four slots on an ATX motherboard full.
Here's some fun facts about DDR5 RAM & Intel CPUs (yes, I'm skipping over some fine-grained technical shit here, don't @ me).
Firstly, when you check motherboard specs, anything over 4800MT/s has "(OC)" after it. The CPUs are specced to 4800MTs, and after that we're talking factory overclocking.
A manufacturer 32Gb (2x16Gb) kit rated to 6000MT/s? That's with Intel's XMP (EXTREME! Memory Profile) turned on. Otherwise that sucker is running at 4800MT/s.
Want 64Gb of DDR5 RAM? Don't... DO NOT buy 2x 32Gb kits to fill out the slots, because welcome to hell.
The kits are sold in 2x[n]Gb [nnnn]MT/s and will run at that speed as a pair.
Your motherboard manual will tell you to install in the slots 2 & 4.
DDR5 is dual-channel RAM, and installing in those slots will get you running at full speed.
See, slots 2 & 4 are daisy-chained from slots 1 & 3 respectively, and if you install in 1 & 3, you can get some signal bounce back from the empty slots, slowing down the RAM. Installing in 2 & 4 means the RAM is at the end of the signal path.
The kicker is what happens when you install a second pair of RAM modules in 1 & 3 when you've already filled out 2 & 4.
You installed a 32Gb kit, a matched pair of 16Gb modules in slots 2 & 4, and XMP is on, and you've got that sweet 6000MT/s factory OC happening.
You start up your PC, and remember WHY you'd initially planned to go to 64Gb of RAM.
Obviously, go and buy a second 32Gb kit, right?
Don't do that.
Uhhh, that signal bounce issue? Yeah, that's still in play.
Install your second kit, boot that sucker up, and...
Reboot, jump into the UEFI, turn off everything to do with the RAM, bringing it down to default speeds, reboot.
OK, it's booting, and the 32Gb of RAM is now running at factory default 4800MT/s.
Shut down, install the second kit, reboot and... it boots!
Jump into the UEFI, and that sweet 64GB of RAM is running at ... 4555MT/s
Wait what?
Yeah, so that signal bounce issue messes up the RAM timing, so the motherboard WILL slow down the RAM until it's stable, and on my motherboard that means running at 4555MT/s.
Turn on XMP, and it won't boot, because the 6000MT/s numbers on the RAM packet are with XMP turned on and with ONLY two RAM modules installed.
With a lot of messing around, I got the system running stable at 5600MT/s, but I'm never going to see 6000MT/s with four RAM modules installed.
Back to the post at the top of the thread.
The pretty Corsair pictures with four sticks of RAM is effectively false advertising. If you want the pretty RGB lights without the "missing teeth" effect of having RAM just in slots 2 & 4, Corsair will sell you a dummy kit to fill out the other two slots. RAM blanks with the lights attached.
If you want 64GB of RAM running at 6000MT/s, then you buy a 64Gb (2x32Gb) kit, and install that.
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