Intel’s 12th generation CPUs were released into the market just less than a year ago, and with them came a few issues around DDR5. This was expected since, at the time, DDR5 was a brand new RAM standard. And we expected a few teething problems.
However, issues with DDR5 persist, with users (including ourselves) experiencing fatal errors with DDR5 on new 12th generation CPUs and motherboards.
Now read: Best Intel 12th gen CPU
Don’t panic, we’re here to give you some friendly advice as this issue plagued one of our in-house PCs for a week or so, and definitely left us scratching our heads for a while. Was it RAM? The CPU? The motherboard? Let’s find out.
Intel 12th gen DDR5 issues
The issue seems to be with DDR5 only. We haven’t seen or experienced any issues with DDR4 on the 12th gen platform. Not only that, we haven’t seen any reported issues coming from the 11th gen platform on LGA1200 either.
For reference, the initial RAM Kit was 16GB of Corsair Dominator DDR5 @5600MHz 40-40-40-77.
What’s the issue?
From what we can gather, the motherboard BIOS (Basic Input Output System) is setting incompatible RAM timings automatically. This doesn’t just happen once, however, as it will continue to do so even after you’ve cleared the CMOS (complementary metal-oxide semiconductor).
This is the component of the motherboard that’s battery-powered, allowing it to retain things like system time and BIOS configurations.
This causes the BIOS to be unable to read the RAM, or outright detect its presence in the first place. All our ASUS Maximus Hero Z690 did all day was throw Q-code 55 all day. Q-code 55 means the motherboard doesn’t detect any installed RAM, here’s a list of fixes we tried.
- Clearing the CMOS
- Updating the BIOS
- Downgrading the BIOS
- Trying different RAM with different speeds and timings
- DIfferent RAM DIMM slots on the motherboard
- Manually changing the RAM timings
- Different CPU
- Enabling / disabling XMP
The interesting thing is that when we attempted to boot with one stick of DDR5 RAM we had no issues, this was with and without XMP being enabled. But this wasn’t the case in every motherboard RAM slot.
When we introduced any stick of RAM to the A2 RAM slot, the fault persisted. So, that’s it, right? Just a dead DIMM slot? Well, no. The A2 DIMM slot works fine with XMP disabled. Suggesting that there’s more at play here than just the BIOS defaulting to incompatible timings.
After all our testing, we just assumed our ASUS ROG Maximus Hero Z690 was dead, or there was something wrong with a memory controller and we ended up sending it off for an RMA. But after some searching on the internet, er found a forum that suggested enabling Gear speed ratios or cranking up the voltage of your RAM by 100mv or so.
Please note: we aren’t blaming anyone for this, especially not Corsair. This is just the RAM brand we found the issue with, the issue also persisted with XPG RAM.
What is gear?
Simply put, the Gear mode is the ratio between the memory and the processor’s memory controller. Intel Gear is exactly as it sounds, it’s about ratios. Gear 1 runs the RAM and the memory controller at the same speed in a 1:1 ratio. Gear 2 runs the RAM at twice the speed of the memory controller in a 2:1 ratio. However, gear 2 comes at the cost of increased latency, but will increase the memory speed supported by the CPU.
Dram voltage increase
If you wish, you can try adding stability to your DDR5 kit, this means you’ll have to adjust the voltages and this is no simple process – it’s more of a mix between fine art, and trial and error. Here’s what’s different between DDR4 and DDR5 if you’ve just made the switch.
- DRAM voltage is gone (at least on this ASUS Maximus Hero z690 motherboard anyway).
- DDR5 introduces on-module power management. Each memory stick has its own power management IC (PMIS) responsible for reducing 5v input from the motherboard to the required DIMM voltages.
- All available PMIC regulation parameters are available under ‘Ai TweakerAdvanced Memory Voltages’ but the two main rails of interest are DRAM VDD and DRAM VDDQ, as these are the only helpful settings for overclocking. The recommended voltage of each is 1.25v so try not to exceed that if you can.
- Each stick of RAM requires different voltages depending on the performance. Some are rated for much higher voltages than others, but as a general rule, we’d never suggest going over 1.5V.
- The recommended voltage baselines for different brands of memory modules are as follows: 1.25v VDD and VDDQ for Hynix, 1.25 VDD 1.35 VDDQ for Micron, 1.35 VDD 1.35 VDD for Samsung.
If you want to try overvolting your RAM, you’ll have to find the Memory VDD Voltages and VDDQ Memory Voltages headings under Extreme Tweaker / Advanced Memory Voltages in the advanced tab of the BIOS. Do not exceed the recommended voltage baselines outline above.
Is it time to RMA?: ASUS Z690s recalled
As we said before, we RMA’d our motherboard, if it’s under warranty then you should consider it. This is especially true if you have an ASUS ROG Z690 motherboard, as all of them were recalled in December 2021 due to a major memory slot design flaw. It could just be possible you have one of the bad boards that were somehow spared the bin.
Although, if you bring this issue to ASUS’s attention, we’re sure they won’t turn you down. They will have a complete list of serial numbers depicting affected products, and it’s worth asking if you have an ASUS Z690 motherboard.
You’re free to try any of the fixes we did to fix your motherboard, but we told you about our experience to save you time and money in the long run. We’re afraid this time an RMA is probably the way to go. We know they’re frustrating and believe me, more than a few of us wanted to turn our Z690 into the world’s most expensive frisbee, but it’s best to let the manufacturer deal with it.
You shouldn’t be outside of your warranty yet, the boards aren’t old enough. But if you are, comment down below, and hopefully, we can find you a solution. We hope you enjoyed this Intel 12th gen DDR5 issues article and hope it helped you somewhat.