Looking for feedback on new PC build

[pfc]

I'm currently using a very old potato for my gaming needs with an Nvidia GPU, and it's going to finally be replaced by a new machine.

Usage/my requirements
It will of course be running Gentoo, and it will primarily be used for gaming (currently mostly 7 Days To Die and Crusader Kings III).

I've decided on a build with AMD CPU and GPU, and I've gotten the suggestion I pasted below from a buddy that's a Windows user. So I'm interested in feedback specific from the Gentoo community.

The GPU must have at least 2 Displayport outputs, and the monitors must have at least two inputs (2 Displayports or 1 Displayport+1 HDMI) as the monitors will also be connected to my work laptop.

It should be as quiet as possible (at least when idle as my current potato sounds like a jet when idle), but no water cooling.


Questions
Is it enough RAM or perhaps overkill in that it will not be fully utilized?

What about the GPU - is it too new, or is it fully supported by the current AMDGPU driver? It's not listed in https://wiki.gentoo.org/wiki/AMDGPU#Feature_support but does that mean it's not supported at all, or is it only old GPU's not listed that's not supported by this driver?

I know it's not possible to see into the future to know which new interfaces will be created, but does it seem likely that this build will be possible to upgrade when the GPU/CPU/RAM requires it, so that I don't need a completely new build with motherboard etc?



Any other comments are welcome as well.



Current idea:

Red items are items previously considered but replaced by something else.

Monitors
2x 27" GIGABYTE M27Q Rev. 2 - 2560x1440 (QHD) - 165Hz - SS IPS - 1 ms

CPU
AMD Ryzen 9 7900X CPU - 12 cores - 4.7 GHz - AMD AM5
AMD Ryzen 5 7600X CPU - 6 cores - 4.7 GHz - AMD AM5 - AMD Boxed

RAM
G.Skill Trident Z5 Neo RGB DDR5-6000 BK C32 DC - 64GB (AMD EXPO)
Corsair Vengeance DDR5-6000 - 32GB - CL30 - Dual Channel - AMD EXPO

Motherboard
ASUS ROG STRIX B650E-F GAMING WIFI Motherboard - AMD B650 - AMD AM5 socket - DDR5 RAM - ATX

Storage
Samsung 990 EVO SSD - 2TB - PCIe 5.0 - M.2 2280

GPU
ASUS Radeon RX 7800 XT TUF OC - 16GB GDDR6 RAM

CPU fan
Noctua NH-D15 chromax.black - Max 24 dBA

PSU
Corsair RM850e V2 (ATX3.0) - 850 Watt - 120 mm - 80 Plus Gold certified

PC case
be quiet! Silent Base 802 TG - Black - Miditower


I'll be reusing my current mouse, keyboard and speakers.

[NeddySeagoon]

pfc,

Here's my Bucket List system.

The rational may be of interest. As its nearly three years old, the parts list less so. Although we have some similarities.
Great minds ...
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[logrusx]

RAM is OK, CPU is not. You should not be saving off of CPU cores. Buy Ryzen 7.

A friend of mine bought two DELL monitors which could act as KVM switch, unfortunately I can't remember the models. Everything went through one USB-C in one of the monitors, the second was connected to the first monitor, they automatically split the picture between them so it appears as a single device. That works on Debian, so it should work on Gentoo too. Unfortunately I don't remember what was the GPU, neither I know how such setup is suitable for gaming. He uses it the same way you intend to except he has more work laptops to connect.

The rest is more or less unknown to me, but having used an old PC for a long time I suspect even a loud new PC will be quieter than the one you currently have. Buy a big cooler with wide fan that spins slower, that'll give you the most piece most effectively. Unfortunately you can't replace the fans on the GPU and if you do, that opens a while other can of worms, so be sure to research how does the GPU you're buying performs noise-wise.

Best Regards,
Georgi

[NeddySeagoon]

pfc,

Your motherboard can take at most 128G RAM.

If you plan to upgrade later, 32GB RAM as two sticks of 16GB may mean that those 16GB sticks get swapped for 32GB sticks later.
With future upgrades in mind, I would fit 64G RAM now as 2x32GB sticks. You could have a single 32G stick if you really wanted but that will slow memory access as the CPU can access two sticks at the same time.

The AMD Ryzen 5 7600X CPU - 6 cores is not very future proof. Software tends to grow to consume all available RAM and CPU cycles, then some.

If you are planning a CPU and RAM upgrade in a few years and donating your planned CPU and RAM to another user, its an OK place to start.
Don't plan on using that system in 10 years time though.

Gentoo will use 2G real RAM per CPU thread for building. You have 12 threads. That's 24G real RAM for gcc.
To have /var/tmp/portage in tmpfs, which avoids writes to you Samsung 990 EVO SSD, you need more RAM, maybe twice as much, so that's 48G RAM.
Avoiding writes to SSD is a good thing for SSD life. It may not matter to you. It all depends an your usage patters.

Samsung 990 EVO SSD - 2TB - PCIe 5.0 - M.2 2280 is a TLC device. That is, each flash memory cell stores three bits of data.
The write life is given as 600 erase cycles. which is typical for TLC devices.
QLC (Quad level Cell) SSDs are around. They store 4 bits per flash cell. They are lower cost, (less flash cells) slower, as the difference between levels is less and are rated less erase cycles. Avoid them unless it is for an application that will be read mostly.
For a general purpose PC, avoid them like the plague.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[pfc]

Thank you both for your feedback, it is a great help.

RAM:
On my current machine I'm using a ramdisk, but hadn't considered that regarding RAM, so that's a very good point, @NeddySeagoon.
With that in mind I doubled the RAM and have this on the shoppinglist: G.Skill Trident Z5 Neo RGB DDR5-6000 BK C32 DC - 64GB (AMD EXPO).

CPU:
I added this one to the shoppinglist based on the advice from you guys to get some more cores (I guess I also doubled those like the RAM): AMD Ryzen 9 7900X CPU - 12 cores - 4.7 GHz - AMD AM5.
Is that overkill, and based on your calculation, @NeddySeagoon, would I then require even more RAM?
My current /var/tmp/portage ramdisk is 17GB which seems to not be a problem (I have 24GB RAM and 8 threads on my current machine) and according to this page the largest package is Firefox with 13GB.
24 threads using 48GB would leave 16GB for a ramdisk with the 64GB RAM.


I used the official support link to find RAM and CPU that was listed as supported, to minimize the risk of experiencing any issues.


SSD:
@NeddySeagoon: Just to confirm - This is a good choice as it has TLC which is better than other disks that have QLC?



Monitors/KVM:
@logrusx: I think my setup should work fine, as the monitors have built-in KVM.
So it seems I just connect one keyboard and mouse to one monitor, and on that monitor have both machines connected with Displayport.
So when I switch between the input on the monitor, the keyboard and mouse controls the one currently being displayed. The other monitor would of course also be connected to both machines.
I'm currently using xinerama (I think) to use two monitors, so I expect to do the same on the new machine, and that would allow me to disable a monitor if necessary which I'm not sure is possible with your friends setup.

[NeddySeagoon]

pfc,

The RAM disk size is not fixed. The 'size' you set is an upper limit to the amount of RAM that it can use.
Should you save some swap space. tmpfs can be swapped out if more real RAM is needed.
When the space is not in use, it can be used for other things.
Its just the kernel disc cache with no permanent place on disk.
Your default tmpfs space will be 32G, its half of RAM.

12 cores, 24 threads, 48G RAM for gcc. Except that will be an over estimate as very few packages, if any will have 24 make jobs in progress that all want 2G RAM each.
That's probably a good thread count. Very few packages will ever get 24 threads building concurrently.
There are a few, like Thunderbird, Firefox, Libreoffice.

Having had to use Samsung's warranty process for two 1TB SSDs that were full of bad sectors before they had even 1TB written, personally. I will never buy Samsung storage products again.
The hoops you have to jump through to get a RMA number is just not real.
That's not a problem once the warranty has expired though.
Samsung have a good reputation, so why not. Maybe I was just unlucky.

TLC Flash is usually guaranteed for 600 erase cycles.
QLC about half that.
The erase cycles as usually expressed as Terebytes Written, so a 1TB TLC device would be 600TBW a 2TB device 1200TBW and so on.

A flash memory cell is an analogue device. Its a capacitor. To store 3 bits of information, the read/write electronics have to distinguish 8 voltage levels.
For QLC the 4 bits require 16 voltage levels.
The more bits per cell, the harder it gets.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[krumpf]

All this discussion about SSD endurance reminded me this experiment.
It's a bit old (from 2013) (and it seems images from the pages were lost in the 404 abyss) but is still interesting to read imo.
The experiment started in august 2013, and ended in march 2015 with the death of the last tested ssd. If you wanna read about the results, scroll to the bottom of the page to find update links (the final result page got a youtube video where you can see a few of the missing images from the website).

Back to topic : maybe you could save a few bucks by using a pcie 4 ssd instead of a pcie 5. The usual benchmarks will show the pcie5 is way faster than the pcie4, but when it comes to loading games, the difference is quite often less than 5 seconds.
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