Gskill 6400 Hynix A die (not M die) best DDR5 in MC stock!

Rs199208 ✭✭
First Anniversary Name Dropper First Comment
edited November 2022 in General Discussion

just wanted to share incase it helps someone...

was presently surprised last week when i purchased what thought would be a Hynix M die 6400 kit from microcenter but it actually turned out to be the high speed low power consumption A die!

i decided to scroll through the dram speeds to see how well this new kit would respond after installing into my 12900KS Z690 MSI Unify X rig.

to my surprise the kit immediately booted into windows 11 after enabling 6400 XMP then choosing dram speed of 7200.

i then kept scrolling up the dram speed till 7800 booted into windows 11!

i still had no idea it was A die at this point...

turns out the labels on the heatsinks are the only tell of which die it is.

820A=A die/820M=M die

you can see this through the cutouts on the back of the kit box of Gskill.

anyway....long story short. i heated up the sticks with a hairdryer, and after a couple minutes i easily pried the heatsinks off the sticks and then installed the dimms into a Bitspower DDR5 water block.

i chose 7200 to stabilize leaving lots of OC headroom, then i began tightening up the timings.

ended up with 45.4ns in Intel MLC, and 47.5ns in Aida64 with 113.9 GB/s.

stable with TM5/Absolute stress test.

the best DDR5 kit i have owned yet! I'm glad it wasn't M die!

SKU: 375238

Mfr Part #: 6400J322X16T5RK

UPC: 848354041368

Trident Z5 RGB 32GB (2 x 16GB) DDR5-6400 PC5-51200 CL32 Dual Channel Desktop Memory Kit F5-6400J3239G16GX2-TZ5RK

i when back to MC to check the other kits, i confirmed that in stock were two different dies of Hynix for 6400, and 6600 each of GSkill.

i already knew 6800 and up were A die before this but big upcharge for just XMP. Hynix doesn't seem to bin lower modules for lower skus.

but you do need to put some work in to get stabilized and higher speeds depending on your MB and CPU capability.

not all MB can do this , 2 dimm ram OC mb are best at this.

MC price matched Newegg sale for me which was $219 for this kit that sale is now over but MC dropped their price to $230 this week!

the HWinfo64 has a A die bug which is why dimm1 shows a false max hub temp of 47.8. its doing this to everyone.


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