Z790-E WIFI ; 14700K ; G Skill 7200MHz 2x16 32GB - XMP stable at desktop, games crash, RAM help

[OleWarChief]

Hello! This is my first time ever posting in a forum so please bear with me, and I appreciate any insights and guidance.

TL;DR - Default XMP crashes my system in gaming with the listed config, though on paper it should be supported. Looking for guidance adjusting the system RAM timings/voltages to optimize performance and stability.

This is my first personal PC build and important milestone of great importance for me. My goal is to have a reliably stable high-performance system. I am open to changes in the Mobo given I have a protection plan. The CPU return deadline ends today 7/3/24. All other components 15 days from today.

This is the setup:

• ROG STRIX Z790-E GAMING WIFI 
• Intel 14700k
• DDR5-7200Mhz 2x16 32GB G Skill Z5 Trident (F5-7200J3445G16GX2-TZ5RS)
• Samsung 990 Pro 1TB with a matching 2TB for games
• ROG Strix LC II 360 AIO, and 6 Lian Li SL-Infinity fans mounted in the Lian Li O11 Dynamic
• KO-RTX 3070 O8G GAMING

I built this PC with default BIOS settings and enabled XMP to run the RAM at 7200MHz CL34-45-45-115 1.40v, which is confirmed on the QVL. My system works well in desktop tasks but freezes when I launch games like Fortnite and COD MW3. The issue persists even after checking various online forums for solutions.

Lowering RAM frequency to 6400MHz made Fortnite stable but COD still crashed. Attempts to tweak CAS Latency to 36 @ 6800MHz helped slightly for Fortnite but caused a lockup during memory stress testing. I am a novice at overclocking but willing to learn. I seek guidance on adjusting values like IMC, VDD, VDDQ, Timing, etc., to enhance gaming stability.

Memtest86 showed no errors, but AIDA64 and 3Dmark caused similar intermittent crashes. I prefer maximizing performance with existing components but am open to hardware changes for future-proofing. Despite feeling discouraged, I remain hopeful for a solution and appreciate any assistance.

Thank you!

[Silent_Scone]

1. Is the system stable at 7200MT in OCCT with Intel Default > Performance Profile set?

2. Karhu is one tool I would gladly recommend you purchase a licence for as it’s invaluable for memory stability testing and not expensive. There is little point tightening down latency if not confirming a certain level of stability.

3. It’s a mixture of all the components combined, all of them will have a limitation. 7200MT on a 4 DIMM board is a reasonable overclock. 

[OleWarChief]

Good morning! Thank you for keeping at this with me,

1. From my Mobo BIOS, in the Advanced -> Ai Tweaker, there are only two options; Intel Default Settings and the ASUS Advanced OC Profile. I use the Intel Default, and I haven't seen an option to choose extreme or performance. The update below lists it as an option in the BIOS, but I do not see the option anywhere. I have tried the ASUS profile only to experience worse system freezes. I am currently on BIOS 2301

2. Understood. I will look into purchasing Karhu and getting some data to share here. OCCT has been my test of choice due to the Memory Stability test reproducing the same results(crash or not) as gaming. However, it doesn't provide granular data to analyze. It simply runs smoothly or crashes within 5s~1.5min depending on the frequency. This has translated to game stability in games as well. The only errors I have gotten in OCCT testing is when I adjust timings too tight at lower frequencies; It immediately obvious because OCCT will error, and system BSODs and reboots normally.

3. Understood, I am gathering that as I learn more, thus my theory that this maybe isn't a hardware capability  limitation but a configuration/timing/voltage issue. I'd like to adjust the voltages for the relevant components up, but not sure the best place to start. I see the VDD, IMC, SA, etc in the BIOS, but I haven't found a write-up online that explains voltage adjustments in a focused way that helps me start tweaking the values. Do you have any recommendations?

*Side note - Is this the best place to be asking these kinds of questions and are these forums still active for this kind of help? This post seems to be getting very little activity or responses from other users compared to those in the past or others experiencing similar issues

[Silent_Scone]

1. That's fine, only the i9 SKU has more than one profile. Intel Default is fine. The clarification on which SKUs are supported is quite vague so some users have been confused on this.

2. Honestly, Karhu is very quick at catching errors. For point of reference I've previously shown that for 3 complete passes of Memtest86+ with no errors, Karhu will last roughly 2 to 3 minutes before producing an error. It's extremely good at isolating the memory bus.

3. See where you are with Karhu before making adjustments to memory-associated voltages. Most users fall over these days understanding just how CPU specific these can be. The higher the frequency, the more likely the need will arise to tune these things manually. Most key on this platform on the CPU side are IMC VDD, IVR and VCCSA.

And yes, this section is for looking for info and guidance. ROG Care is predominately for issues best dealt with by customer service.

[OleWarChief]

Hey @Silent_Scone! Sorry for the delay, was out of town. However, I do have some new developments since the last post and wanted to get your insights. I have not purchased Karhu yet, but this will be a next step in fine tuning the RAM. Ideally I can optimize and gain a high rate of stability, the system is mostly stable during testing/games now but did have some hiccups over longer term use.

Side note - I have since swapped to the Corsair Dominator Titanium kit and returned the originally referenced GSkill kit. They both worked with the information below, but the Corsairs beat the GSkill in every benchmark I did in AIDA across every OC and stock speed, were more stable, and offer a XMP profile for 7400Mhz for future growth(more on that below).

I was able to get the RAM to work without errors and immediate crash/system freeze in OCCT at ~7200MHZ by adjusting some voltages based on advice I saw in another post you had chimed in on. These are listed below:

VDD Voltage(XMP/Stock) - Corsair = 1.45v ; GSkill = 1.40v

VDDQ Voltage (XMP/Stock) - Corsair = 1.45v ; GSkill = 1.40v

CPU System Agent Voltage - 1.2v ~ 1.25v (changed from BIOS Auto at 1.3v) Adjusting this down seems to have a big impact on system crash and stability.

IVR Transmitter VDDQ - 1.4v

Memory Controller -  1.3v ~ 1.35v

Some of this may be a tad off because I am referencing it from memory and what I based my testing voltages off, but they are very close. The main manual change was the IVR - 1.4v ;  SA - 1.2v~1.25v ; IMC - 1.3v ~ 1.35v

My question is, are these voltages safe? and are you able to provide guidance on why turning SA down seems to help? Also what would fine tuning with this voltages look like? or just use as is?

I passed 1 hour on each kit at 7200MHZ in OCCT memory stress test. I even had success at XMP 1 at 7400MHZ on the Corsair for around 15 minutes, but once the temps hit 60c I received 1 error that increased to 2 errors as the temps rose. I stopped the test given it was out of scope for my goal and it was more for proof of concept.

I will be battle testing the Corsair going forward this week at 7200MHZ and will report back.

I had gamed for several hours on the GSkill at 7200MHz before I started getting crash to desktop, but no system freeze. However the system locked up with errors after the gaming session in OCCT but passed the next stress test after reboot. I think this may have been due to a pending Windows update but not sure.

My goal now is to make sure the kit works at 7200MHZ stable for gaming and then I will be satisfied and then tinker more if time is willing or with hardware/BIOS updates.

*Kit Information -

GSKILL- DDR5-7200Mhz 2x16 32GB G Skill Z5 Trident (F5-7200J3445G16GX2-TZ5RS)

CORSAIR - DDR5 -7200MT/s 32GB (2x16GB) CL34 DOMINATOR TITANIUM RGB (CMP32GX5M2X7200C34)

[Silent_Scone]

Hi @OleWarChief 

1. Those voltages are fine.

2. 1-hour OCCT is likely enough stability margin for a gaming rig.

3. VCCSA (System Agent) is a signal rail sensitive to voltage changes - auto rules may need adjusting with manual tuning for some CPUs, especially on high-frequency kits. We saying "tuning" and not raising because more voltage can cause instability depending on the CPU sample.

4. Where possible, try to keep temperatures below 50C. Active cooling with a fan can make the difference between a pass and fail depending on stability margins.