If I may offer some genuine advice, it would be that the tone of your original question (and subsequent answering) is what triggers this rather unfriendly atmosphere in the thread.
Firstly, instead of posing a genuine question, you start by doubting advice given by somebody else who has actually already given the correct answer. The premise of the question is founded on disbelief rather than for example: "you tried it, and it still worked". The second part is intrinsically fine, but does demonstrate the lack of a broader perspective other than your own use case.
The latter parts of the thread where you go on to describe that reading a manual is too long, not bothering to get to the physical manual, or looking for a copy online just gives the impression of general laziness which isn't particularly inviting for a positive response.
How you use the forums is of course up to you, but remember that those answering are also human beings. And so if you ask questions that could be easily answered by reading the manual, expect that also to be part of the answer provided.
I think you'll be pretty hard-pressed to have someone with a Z390 ACE respond to your thread in a timely manner.
And even then, how many people with a Z390 ACE (or any other board for that matter) actually know exactly which M.2 slot would disable which SATA port when occupied?
Because what M.2 slot disables what SATA port is not standard, every motherboard does it differently, so everyone answering would basically be doing what you could've done in the first place - check your specific motherboard's manual.
I meant in general. You've asked about a few different monitors a few times.
Going to a local store and looking at a few monitors is a good place to start even if it's not the exact monitors you see online.
Do they have it or a monitor with similar specifications in a local store? If so, go there and have a look at it if lockdown restrictions allow that.
If they don't have it then have a look at monitors there anyway, doesn't have to be a similar monitor.
Known internally as the 2020 "Craptop replacement build"
Why is it called the "2020 craptop replacement build"? For starters, until I got this system, I ran my entire setup off a laptop (specifically, an ASUS ROG STRIX GL502VM). Powered by a duo consisting of a Core i7 7700H and a GTX 1060 6GB, it proved to be just about powerful enough for what I needed it for, which is gaming and photo editing although video editing proved to be a bit of a chore over time.
Anyway, those didn't matter because this year, it started giving off FAULTY_HARDWARE_CORRUPTED_PAGE BSODs. After multiple diagnoses with no clear solution in sight, I threw in the towel after it seemed to keep bluescreening with increasing frequency. For the new build, it had to meet the following criteria;
It needed to be suitable for a hybrid productivity and gaming workload
It needed to be reliable enough for sustained use over a period of time
It needed to have a bit of an upgrade path for more storage and such should it be required
It should cost no-more than $2000 for the tower itself, not including monitors and such (since they were already part of the setup)
After some time planning, asking around, looking at reviews and making and refining PC Part Picker lists, I came up with this. Bear in mind that the parts are a direct conversion of the local prices here, which is in Malaysia, so it may be inflated compared to pricing in America (or deflated given what's going on lately).
CPU: This one was a relatively easy pick. I had initially wanted to go with the Ryzen 9 3900X for its 12 cores and 24 threads, but doing so would've gone over-budget and needed for me to skimp on some other components. So I went with the 3700X as it still maintains excellent performance in productivity tasks whilst also being very good for gaming loads. I had considered the 3800X but for $50 more, the small bump in performance was not worth it.
Cooler: I went air-cooling mainly for the simplicity alongside reliability. Choosing one was surprisingly difficult due to how we don't really have that many options. I initially thought of the quite-mediocre Cooler Master MA620P until I saw that the Dark Rock 4 and its Pro variant were in stock. I went with the Dark Rock 4 due to its smaller footprint. Combined with Thermal Grizzly's Kryonaut paste, the combination proved to break absolutely no sweat with the 3700X, maintaining 63-65 degrees during a Prime95 Small FFTs stressload. The case has a CM SF360R kit of 3-in-1 120mm fans as intakes with the 2 included case fans being used as a rear and top exhaust.
Motherboard: This one took a bit of time to decide. The MSI B450 Tomahawk MAX was my initial pick but it was pretty much impossible to find in-stock. Upon finding out that the ASUS TUF Gaming X570-Plus was in stock (the only good $200 AM4 board in stock at the time), I grabbed it. The TUF isn't particularly feature-packed but it is also a rock-solid board.
RAM: Let's be honest, I'm not a fan of RGB memory but it was difficult to find good 16GBx2 kits at all, let alone non-RGB ones. The SPECTRIX D60Gs were the best ones available and they have performed quite well so far, being stable at XMP speeds and also has some headroom for tuning and overclocking if I so choose to despite its Hynix CJRs being not nearly as forgiving as variants with the venerable B-dies from Samsung. And I may or may not be allured by the RGB....just a bit....I swear.
Storage: To save on cost, I repurposed the XPG SX8200 Pro that I had gotten as an upgrade for my laptop. It's a great speedy SSD that I got for a reasonable price. Mass storage as of this time is handled by a Seagate Barracuda Compute 2TB hard drive, with a future 1TB Crucial MX500 SSD being planned in the future for game storage.
GPU: This one took months due to the big GPU shortage of 2020 from human malware. Many GPU variants were not in stock, notably 2070 Supers. Tracking one down proved to be difficult and the ones that were in stock were either fitted with mediocre coolers or were just plain overpriced in 2080 Super territory. After nearly a month, I finally managed to track down a Gaming X Trio AIB version of the 2070S. The card is absolutely MASSIVE but it really does perform, maintaining 65-67 degrees in games without making any noise louder than a silent whirr with clockspeed boosted to 1950MHz.
PSU: I got real lucky with this one. The great PSU shortage has caused many PSUs to not only be out of stock but also inflated their prices to such extremes. However, I managed to snag an in-stock RM750i for MSRP, which was a real lucky find. From the beginning, I knew my build needed to be powered by a quality PSU and while 750W is quite overkill for this set of hardware, a benefit is that during heavy loads, the PSU is pretty much near its peak efficiency.
Case: I initially had looked at NZXT's H510i as I am enamored by its clean design but was concerned about its limited airflow. Due to that, I also looked at the H500P Mesh until I stumbled across the NR600 in a Gamers Nexus video. Given that it looked to combine the NZXT's aesthetic with great airflow, I knew that no matter what, I had to get that case. And as luck would have it, it shortly came back in stock, and I got it. Great performance in terms of airflow and while it's not the nicest to build in, there are still solid cable management points although I did get quite a lot of help with that.
OS: Just repurposed my ancient Windows 7 Ultimate license. Got Windows 10 Pro without an additional upgrade fee.
So far, everything works perfectly. I'm planning further upgrades like the aforementioned SSD alongside a third monitor like the LG 27GL850 listed in the part list.