DDR4 Question

[Jedimaster]

Dear all I need your help - as Im a little bit lost. I ordered an i9-7900x wit an ROG x299 Rampage Extreme mainboard allowing DDR4 up to 4200+ and more. So what I actually want is G.Skill RGB RAM and for sure 32GB. As this is a quad channel board i will need to go for 4x8GB. Now my question: What would you recommend? Your precious help is welcome.

*Thirst I wanted to buy this Dual-Channel kit twice time to get 32GB: G. Skill RGB: 2x8GB 4266 with CL19-19-19-39 (not QVL)

Couple of days I have seen a new kit coming out in december for official quad channel (but actually I need them now and dont want to wait until Xmas): G.Skill RGB: 4x8GB 4200 with CL19-23-23-43-43 Whats the difference? Are this guaranteed timings for quad channel? So if I would go with twice dual-channel now - I would need to optimize timings and also get same performance? Or do I miss something...

Alternatively I could go with official quad channel kits: G.Skill RGB: 4x8GB 3600 CL16-16-16-32 (QVL) or G.Skill RGB: 4x8GB 3866 CL18-19-19-39 (not QVL)

QVL says officially 3600 as max for 4Dimm solution...every faster ram is only listed as 8Dimm solution. Thx for your feedbacks/thoughts. Very appreciated! Best, Jedimaster

[Korth]

QVL means ASUS tested and confirmed compatibility.
Not-QVL means it's untested and (in)compatibility is unknown.
ASUS QVLs typically get revised with additions over time. But ASUS simply cannot test every RAM stick and kit model released by every manufacturer.

I'd stick with QVL, personally. Or read/watch guides and get whatever the reviewers and overclockers get.

And I wouldn't expect over-rated DDR4 kits to actually perform for daily use at their advertised speeds, especially not at the upper extreme.

[rzotti]

Jedimaster wrote:
Dear all I need your help - as Im a little bit lost. I ordered an i9-7900x wit an ROG x299 Rampage Extreme mainboard allowing DDR4 up to 4200+ and more. So what I actually want is G.Skill RGB RAM and for sure 32GB. As this is a quad channel board i will need to go for 4x8GB. Now my question: What would you recommend? Your precious help is welcome.

*Thirst I wanted to buy this Dual-Channel kit twice time to get 32GB: G. Skill RGB: 2x8GB 4266 with CL19-19-19-39 (not QVL)

Couple of days I have seen a new kit coming out in december for official quad channel (but actually I need them now and dont want to wait until Xmas): G.Skill RGB: 4x8GB 4200 with CL19-23-23-43-43 Whats the difference? Are this guaranteed timings for quad channel? So if I would go with twice dual-channel now - I would need to optimize timings and also get same performance? Or do I miss something...

Alternatively I could go with official quad channel kits: G.Skill RGB: 4x8GB 3600 CL16-16-16-32 (QVL) or G.Skill RGB: 4x8GB 3866 CL18-19-19-39 (not QVL)

QVL says officially 3600 as max for 4Dimm solution...every faster ram is only listed as 8Dimm solution. Thx for your feedbacks/thoughts. Very appreciated! Best, Jedimaster

I did something very similar you intended - but regretted it. I got 2 gskill 2x8gb 4266 kits . So far: 1) I am not able to use them together at 4266. The most I am able to boot is at 4000 - non-stable and 3800 - kind of stable. You can now understand why their 32gb kits are clocked at 3866 :-). 2) At safe mode timings, my computer freezes everytime - even at the BIOS. 3) At optimized settings, I still get random freezes now and then. I am not sure this board likes these memory sticks at the current bios iteration.

My recommendation is to wait before getting these sticks / go for the 32gb 4266 kit to be released in December. Or try different ones, like the corsair dominators. If you really want to stick with Gskill now - I would go for whatever is on the QVL.

[Nate152]

Hi rzotti

Sometimes you get lucky mixing ram kits and sometimes you don't, it's best to purchase a single 32GB kit.

You may be able to get it stable setting it manually and upping a few voltages. 32GB at 4266MHz, Dram voltage will likely need 1.40v or up to 1.50v max.

You could also try raising the cpu system agent voltage and cpu vccio voltage anywhere from 1.20v - 1.30v.

Max CPU VCCIO voltage 1.30v
Max CPU System Agent voltage 1.35v
Max Dram voltage 1.50v

See if raising these voltages help get you stable.

[Raja]

Nate152 wrote:
Hi rzotti

Sometimes you get lucky mixing ram kits and sometimes you don't, it's best to purchase a single 32GB kit.

You may be able to get it stable setting it manually and upping a few voltages. 32GB at 4266MHz, Dram voltage will likely need 1.40v or up to 1.50v max.

You could also try raising the cpu system agent voltage and cpu vccio voltage anywhere from 1.20v - 1.30v.

Max CPU VCCIO voltage 1.30v
Max CPU System Agent voltage 1.35v
Max Dram voltage 1.50v

See if raising these voltages help get you stable.

I would not advise jacking voltages like this for X299. Best to stick to what the platform can handle without needing these type of voltages. With a capable single kit, DDR4-4133 is about it on most boards and CPUs. After that, the trade offs are severe.

[mpoffo]

I know this 32GB kit is not up to the speeds you want but I have had no issue with it on the Extreme even though it is not listed on the QVL.

http://www.gskill.com/en/product/f4-3200c16q-32gtzr

[Chino]

If you're really set on getting a very hi-speed 32GB kit, I'm using the Vengeance® LPX 32GB (4 x 8GB) DDR4 DRAM 4133MHz C19 Memory Kit - Red (CMK32GX4M4E4133C19R) on my Strix X299-E Gaming motherboard. As long as your CPU's IMC is capable, I don't see you having problems from a compatibility standpoint on the motherboard you've chosen.

[Jedimaster]

Dear all

Thx a lot for your messages and feedback! I think Ill gonna go for a kit of QVL 3600 4x8 or non QVL 3866 4x8, as I want to build my rig next week. Waiting until dec is to far for the 4200 and I suppose the speed increase from 3600/3866 to 4200 is not significant.

But what wonders me is that on the QVL list are some kits with 8x8 and 4000/4200 listed. I always thought more ram bars are stressing more the board. So it would be more logic to have also 4000/4200 with 4x8...but theres none on the list?

So I ckecked G.Skill product portfolio and its true: 8x8 kits 4000 are availble, but no 4x8 4000? 8x8 is too expensive for me...*

[Moloch]

Jedimaster wrote:
Dear all

Thx a lot for your messages and feedback! I think Ill gonna go for a kit of QVL 3600 4x8 or non QVL 3866 4x8, as I want to build my rig next week. Waiting until dec is to far for the 4200 and I suppose the speed increase from 3600/3866 to 4200 is not significant.

But what wonders me is that on the QVL list are some kits with 8x8 and 4000/4200 listed. I always thought more ram bars are stressing more the board. So it would be more logic to have also 4000/4200 with 4x8...but theres none on the list?

So I ckecked G.Skill product portfolio and its true: 8x8 kits 4000 are availble, but no 4x8 4000? 8x8 is too expensive for me...*

FWIW, I haven't seen anyone successfully hit 4200 with decent timings (except for 1 guy who claims he did it with 1.65v). When I tried to hit 4200, it was not stable at 1.4v, and I had to loosen my timings so much that I had a 25% loss of memory bandwidth compared to 4000

I'd recommend setting your goal at 4000 (even sticks rated at 4200 probably wont be stable beyond 4000 due to motherboard/CPU limitations). That being said, most sticks rated for 3600 should be able to hit 4000 easy enough. My sticks are corsair 4x8 3866, and hit 4000 on the first try. I got the 3866 because it was on sale. Currently the best deal on newegg for 4x8 is g.skill 3600 for $367. Someone in another thread got a similar g.skill set to 4000:

YC2CHUR wrote:




4000Mhz 17-18-18-41-1T, tRFC 37 (1.370v / F4-3600C16Q-32GTZR)

[Jedimaster]

Dear all

Time passed, as I finally did setup my rig yesterday. So with standard settings everything works fine. What is frustrating me is that I changed settings to XMP (3866) for my RAM and system did boot and works stable in Win 10...BUT: Sideeffect is that USB don‘t work anymore. Impossible to connect a device...like the whole bus crashed. How is this possible? Any idea? Thx a lot and best