Troubleshooting RAM XMP Not Booting or Instability
One of the first things you need to do on your new PC is enable XMP/DOCP/EXPO for your RAM so you can run it at the advertised frequencies and timings. The process is however not as painless as the manufacturers make it seem since you can be faced with a blue or black screen after enabling XMP leading to a lot of confusion.
While technically XMP should work out of the box this might not be the case, and if you are faced with such a situation here are some things you need to know and try to fix the issue.
Update BIOS and Reset CMOS
The very first thing you should attempt when your RAM simply won’t run with the advertised XMP settings is updating your BIOS, or if you are on the latest BIOS versions, CMOS reset your motherboard.
RAM compatibility improves with updated BIOS versions and in certain cases, by simply updating your BIOS you can achieve RAM stability while using XMP. In other cases, even with a new BIOS, you would want to reset your CMOS once to reset the values to complete defaults and cycle your system. This process also increases your chances of booting into Windows with RAM XMP settings.
Manual Settings
If your RAM won’t boot or is unstable no matter the BIOS version you are running it is perhaps worth a try to manually set the frequency to what it is supposed to be. To do this go into your BIOS and enable XMP so the timings apply but set the RAM frequency manually. If it still won’t boot, try also increasing the RAM voltage by a small amount (ex: 1.325v ->1.35v). Some RAM kits simply need a bit of a jolt to get going.
If all you see are black screens, try running lower frequencies with default voltage and then with increased voltage (ex: XMP @ 3800MHz to 3600/3200/3000MHz). This should alleviate some of the burden on the kit and allow you to boot. If none of these changes work for you, you might also have to run looser timings on your kit to get the RAM to somewhat perform.
If you are out of luck until this point you are faced with 2 difficult choices: run your RAM without XMP and suffer the loss in performance, or fully tune your RAM manually which is complicated and takes a lot of time. If you do commit to manually tuning your RAM your time investment can produce performance equal to or better than that of your XMP profile.
Things to Consider Before Buying a RAM Kit
Although anybody can be faced with this issue there are steps you can take to prevent having to deal with corrupted data and black screens. The easiest way is to look at your motherboard QVL list which should technically guarantee 100% RAM compatibility. In some cases this is still not true so take the QVL list with a grain of salt.
You could also look at what RAM kits people with similar builds are using and try to get the same one in hopes of good compatibility. Buying a decent motherboard that can run high-frequency RAM and buying a good RAM kit will in itself be a safeguard against even basic XMP profiles not running.
Another important spec to look at is what is the maximum RAM frequency the CPU you are using can run. This is determined quite early during reviews and usually is a bit higher than the official spec (the spec says 3200MHz but all said CPUs can run 3600MHz if the RAM kit/motherboard is not garbage). The memory controller on CPUs is just a lottery so maybe praying before buying a CPU in hopes of good RNG and a stable memory controller might help too!
In short buying good parts (higher spec/higher frequency compatibility) will in most cases guarantee base XMP booting without issues. Once you are booting and your RAM looks stable I would still insist on running some RAM stress tests to ensure 100% stability during operation.