Upgraded Ram to 32GB Gskill DDR4 3000Mhz and now OC is unstable...

[Vayne4800]

So I have been stable on this OC for 3 years (like AIDA64 FPU, cache and Realbench 8 hour stable. Oh and +1800 on HCI memtest):

- CPU: 4200Mhz (42x100) @ 1.265V
- Uncore: 4000Mhz @ 1.255V
- 16GB 2666Mhz 15-15-15-35-T1 @ 1.275V on 100Mhz STRAP.
- Agent is on auto (0.88v), Input Voltage: 1.90V, SVIDs disabled, Spread Spectrums disabled, VCCIOs at 1.1V, Speedstep disabled, FIVR Disabled and other setting at High Performance. BIOS ver. 1302.

It was stable with all the BIOS updates including 3504.

Now I bought 32GB DDR4 3000Mhz from Gskill 15-15-15-35-T2 with Hynix chips. Obviously the ram refused to work on strap 100 for obvious reasons. So I managed to get it on 125 working fine and it gave me HCI memtest of +1000%. Ofcourse I changed the multipliers to 125x34 (4250Mhz) and cache to be as it was before which is 4000Mhz. I even upped the Vcore and Vcache all the way up to 1.3v on both. I can barely do +2 hours of realbench now. The new bios even increases VCCIO CPU 1.05v to 1.25V if set on auto. I always had the Digi+ stuff on default minus the spread spectrum being disabled. I noticed there are a plathora of new settings since my last BIOS and medling with the BIOS. Already spend days trying to get this working, all because I wanted a bit of extra RAM. Hell, I even tried 100 strap and having the ram on 2666Mhz and similar old settings but it won't boot. I played with SA and still nothing. Now I am totally lost and feel this motherboard, bios, chipset are ****ton of headache and confusion than actual OC effort supporting...

Help...

[chevell65]

Have you tried bringing up system agent voltage? Should help to get the memory stable. 1.15 to start..

[Vayne4800]

chevell65 wrote:
Have you tried bringing up system agent voltage? Should help to get the memory stable. 1.15 to start..

Yep, I tried values from .89v all the way to 1.15v. Won't boot (in case of 100 strap) and doesn't help stability in realbench (in case of 125 strap).

[Chino]

Are you only using the new kit or did you combine kits?

[Vayne4800]

Chino wrote:
Are you only using the new kit or did you combine kits?

New kit. 4x8GB. All on red.

[samboy87]

i have the same problem with my 16gb DDR4 3000mhz Gskill. on 100strap with the same settings as 125strap it won't boot, only getting QC B7, but with default XMP it works perfect and stable even with 4.3ghz on the processor. And i even tightend the timing on 3000mhz @ 14-14-14-34-1T without a problem. XMP is doing some magic that i don't know of. but offcourse i would rather be on 100straps and adaptive voltages.....

[xkm121]

I assume you are using Haswell-E. HWE hates 100BCLK with DDR4-3000. Try either 3200 or 2666 on 100BCLK.

[Vayne4800]

xkm121 wrote:
I assume you are using Haswell-E. HWE hates 100BCLK with DDR4-3000. Try either 3200 or 2666 on 100BCLK.

That is what I did. I went back to 100BCLK and 2666Mhz. DDR voltage I left at an abundant 1.3v and used tight timings of 14-14-14-24-T1 (Mode 1). I even upped the vcore to 1.27v and vcache to 1.26v (0.05v above my last stable configuration). HCI memtest passed with flying colors. While Realbench was stable all the way until it finished in which it went to a black screen crash. Do note that I have SLI 1080 Ti FE and I am guessing that is the reason for that. Another thing I am guessing is my CPU overshot voltage when going from load to idle (LLC was on auto) and I did notice that voltage was oscillating between 1.280v and 1.296v in AIDA64.

I honestly don't mind running at 2666Mhz as the price different between the rated 2666Mhz and 3000Mhz is negligible and I can do tight timings on my 2666Mhz.

What bothers me is that black screen crash in realbench (2.54) when the test finished its 8 hour run. Is it SLI or is it CPU voltage overshoot (and therefore I should set some sort of LLC)?

As a bonus, I can do 3200Mhz on 100BCLK if I tweak SA (about 1.02v) and up DDR voltage to 1.40-1.45v with timings 17-18-18-38-T2 (Mode 1). It takes a while to boot but it just tells me that it is doable.

I would appreciate some feedback from Chino on the realbench issue as I haven't seen any official response to that.

[Zka17]

Black screen in RB... are you sure that it isn't your graphics driver?
What is your Event ID?
Do you have any GPU tweaking software running in background? Or any monitoring software? If so, turn them off RB'ing...

[Vayne4800]

Zka17 wrote:
Black screen in RB... are you sure that it isn't your graphics driver?
What is your Event ID?
Do you have any GPU tweaking software running in background? Or any monitoring software? If so, turn them off RB'ing...

When I rebooted the PC, I was asked to press F1 due to a failed OC. So it seems to me that the OC caused it. My graphics drivers are the latest from nVidia. The event ID is 6008. Using Afterburner.