JEDEC and XMP - I want real numbers, not overclocked XMP

[petar]

I am looking into Trident memory:

G.Skill Trident Z silver/red DIMM kit 128GB, DDR4-3200, CL16-18-18-38 (F4-3200C16Q2-128GTZ) [

It is declared as follows:

Type: DDR4 DIMM 288-Pin • Modules: 8x 16GB • JEDEC: PC4-25600U • Voltage: 1.35V • Special features: Intel XMP 2.0 (extreme Memory profiles) • Warranty: lifetime (10 years in AT/​DE)

I will not use XMP, so I wonder if the RAM will still work on 3200 as declared or some lower settings ?

I have seen official settings, but I also seen people on forums saying they can't reach 3200 without XMP. So what is it then ??


Thanks

 

[Mr Kagouris]

JEDEC standard speed for DDR4 is 2133MHz. Manufacturers literally cannot release anything clocked higher by default if they want JEDEC certification.

I'm not sure exactly what your issue with XMP is. It doesn't affect anything except the RAM.

 

[petar]

It raises vDIMM and adjusts VTT maybe even higher than necessary and I don't want that.

 

[Mr Kagouris]

Raising vDIMM and VTT is kinda necessary for those speeds you know. Even if you were to manually overclock to that point you'd get just under the vDIMM and VTT the XMP profile sets (heck, depending on the sticks you might end up with the exact same settings).

 

[madmatt30]

It raises vDIMM and adjusts VTT maybe even higher than necessary and I don't want that.

then you can try & tinker with settings manually or run it at 2133mhz.

Without using the preset xmp profiles that will be the same scenario with ANY ram rated at over 2133mhz as Mr Kagouris has already stated.

 

[Tradesman1]

Obviously looking at X99, not sure what CPU, but the CPUs are 'rated' for 2133 DRAM, what actually determines what you can run is the MC (memory controller) in the CPU and all CPUs (say 6800ks) are individual, some OC great others don't - Silicon Lottery, the same is true of the MCs in each individual 6800K, some are very strong, others not much. Most all X99 CPUs can handle DRAM higher than they are rated for while at stock (the CPU) say they can run 2400, 2666 even 2800 and higher with some. Generally when you get up around 2800 and 3000 it may require an OC of the CPU and/or voltage adjustments to run the DRAM to full spec (say 3200). The XMP profile itself doesn't do this, it's simply the info on the sticks that the BIOS takes in and uses to set the DRAM up. Many BIOS are written to 'assume' that voltage adjustments will be needed so the BIOS makes the changes. What you can do is enable XMP which will set the base, secondary timings and Data rate for you, then adjust the voltages manually (if needed or you so desire), another option is to manually set the sticks up (though not many are comfortable adjusting timings (especially secondary)

 

[petar]

yes thanks, I expected this kind of replies; it didn't change much from the past.

Btw, processor I plan with this memory would be Xeon E5 2683.

 

[Mr Kagouris]

Why buy high speed RAM anyway then though? You're better off getting ECC if the mobo supports it too.

 

[Tradesman1]

Have you decided on a mobo? and which Xeon they have the 2014 v3 and the 2016 V4 of that. Either will prob limit you to 2133 or 2400 DRAM at best unless you really want to play with voltages at 128GB

 

[petar]

Xeon 2683 V4. Motherboard I already have is ASRock X99 WS. It's meant for non-stop virtualization, 8 VMs minimum - so memory bandwidth does matter, ECC mem is no, too slow and not necessary according many articles on the web. So then if necessary, I will appy XPM voltages...

Right now I have X79 with 64G Kingston (non reg, non ecc) and it is 24/7/many_years machine, no single issue ever. I managed to get declared speeds without XMP (chipset was way too hot with XMP settings, water cooling wasn't option, memory was way to hot, decent CPU cooler helped - anyway I wanted to know how are things now with DDR4).

 

[scuzzycard]

I am looking into Trident memory:

G.Skill Trident Z silver/red DIMM kit 128GB, DDR4-3200, CL16-18-18-38 (F4-3200C16Q2-128GTZ) [

It is declared as follows:

Type: DDR4 DIMM 288-Pin • Modules: 8x 16GB • JEDEC: PC4-25600U • Voltage: 1.35V • Special features: Intel XMP 2.0 (extreme Memory profiles) • Warranty: lifetime (10 years in AT/​DE)

I will not use XMP, so I wonder if the RAM will still work on 3200 as declared or some lower settings ?

I have seen official settings, but I also seen people on forums saying they can't reach 3200 without XMP. So what is it then ??


Thanks

Xeon 2683 V4. Motherboard I already have is ASRock X99 WS. It's meant for non-stop virtualization, 8 VMs minimum - so memory bandwidth does matter, ECC mem is no, too slow and not necessary according many articles on the web. So then if necessary, I will appy XPM voltages...

Right now I have X79 with 64G Kingston (non reg, non ecc) and it is 24/7/many_years machine, no single issue ever. I managed to get declared speeds without XMP (chipset was way too hot with XMP settings, water cooling wasn't option, memory was way to hot, decent CPU cooler helped - anyway I wanted to know how are things now with DDR4).

You can always get overclocked speeds without enabling XMP. You just have to have the patience to test every single primary, secondary, and tertiary timing and voltage yourself. I personally don't buy into XMP rated speeds because they are always at 1.35V. If you run low-buck memory rated at 1.2V at 1.35V you can often get similar results. In my case, I have Crucial DDR4-2400 RAM running at 2666, 12-12-13-28, CR1 and tightened secondary and tertiary timings at 1.35V. While I can't get higher than 2666 without stupid and dangerous voltages, the overall performance of 2666 CL12 matches that of more "gimmicky" kits rated for 3000 CL15/16 and such.