F5F Stay Refreshed Hardware Desktop New Build: CPU and Motherboard Compatibility with RTX 3090

New Build: CPU and Motherboard Compatibility with RTX 3090

New Build: CPU and Motherboard Compatibility with RTX 3090

P
pfau19
Junior Member
24
12-28-2025, 10:25 AM
#1
Hello,
I’m assembling a new PC and am open to using second-hand components because I want to save costs while still getting quality. My main use is gaming, but I also need it for scientific computing, especially AI, which is why I chose the 3090 with 24GB of memory. I found a reasonably priced used RTX 3090 and had it tested for me—it performed well.

My current system is quite outdated, so most parts are beyond reuse. I’m considering:
- A case (either old or new, based on other components)
- CPU
- RAM: aiming for 2x16GB or 2x32GB, though I’m targeting 64GB if possible
- Motherboard (I already have Ethernet)
- Fans – I want reliable control and quieter models if needed
- PSU – I have an 850W unit from a previous purchase; should I upgrade it?
- Storage – NVMe drives, size 1 or 2 TB

I’m open to buying used parts if it makes sense, but I still want to keep costs low. I prefer non-RGB/blinking components and don’t need a liquid cooling setup or a fancy case appearance.

I’ll be running Omarchy/Arch as well as Windows (10 or 11).
Since I can’t assume your setup was fully configured for me, I’m mainly seeking advice on CPU/Motherboard and whether replacing the PSU is wise for safety.

Thanks in advance!
P
pfau19
12-28-2025, 10:25 AM #1

Hello,
I’m assembling a new PC and am open to using second-hand components because I want to save costs while still getting quality. My main use is gaming, but I also need it for scientific computing, especially AI, which is why I chose the 3090 with 24GB of memory. I found a reasonably priced used RTX 3090 and had it tested for me—it performed well.

My current system is quite outdated, so most parts are beyond reuse. I’m considering:
- A case (either old or new, based on other components)
- CPU
- RAM: aiming for 2x16GB or 2x32GB, though I’m targeting 64GB if possible
- Motherboard (I already have Ethernet)
- Fans – I want reliable control and quieter models if needed
- PSU – I have an 850W unit from a previous purchase; should I upgrade it?
- Storage – NVMe drives, size 1 or 2 TB

I’m open to buying used parts if it makes sense, but I still want to keep costs low. I prefer non-RGB/blinking components and don’t need a liquid cooling setup or a fancy case appearance.

I’ll be running Omarchy/Arch as well as Windows (10 or 11).
Since I can’t assume your setup was fully configured for me, I’m mainly seeking advice on CPU/Motherboard and whether replacing the PSU is wise for safety.

Thanks in advance!

H
Hagnarock
Senior Member
434
12-28-2025, 10:25 AM
#2
What is your financial plan? Do you need significant processing power from the CPU? From which area are you acquiring components?
H
Hagnarock
12-28-2025, 10:25 AM #2

What is your financial plan? Do you need significant processing power from the CPU? From which area are you acquiring components?

I
Indian_Beast
Member
226
12-28-2025, 10:25 AM
#3
Budget: 700-1000$ sounds reasonable, right? If absolutely necessary, I can save more over a month and raise it. (I might actually manage to get my 64 GB for under 300$ if things go well.)
Threaded Performance: Unless gaming really benefits from it (I’m not sure), then not. For all the other tasks I don’t need it.
Region: Switzerland or any place that can ship to Switzerland.
I
Indian_Beast
12-28-2025, 10:25 AM #3

Budget: 700-1000$ sounds reasonable, right? If absolutely necessary, I can save more over a month and raise it. (I might actually manage to get my 64 GB for under 300$ if things go well.)
Threaded Performance: Unless gaming really benefits from it (I’m not sure), then not. For all the other tasks I don’t need it.
Region: Switzerland or any place that can ship to Switzerland.

E
Eliteoctoling
Member
50
12-28-2025, 10:25 AM
#4
The exact 3090 model currently available is the NVIDIA Founders Edition GeForce RTX 3090 24 GB Video Card.
E
Eliteoctoling
12-28-2025, 10:25 AM #4

The exact 3090 model currently available is the NVIDIA Founders Edition GeForce RTX 3090 24 GB Video Card.

C
Cyanstrophic
Senior Member
668
12-28-2025, 10:25 AM
#5
Oh no, it seems I missed my response. I assumed you had already replied. My Asus TUF RTX 3090 is ready—I'll confirm if this GPU will work.
C
Cyanstrophic
12-28-2025, 10:25 AM #5

Oh no, it seems I missed my response. I assumed you had already replied. My Asus TUF RTX 3090 is ready—I'll confirm if this GPU will work.

M
mcDavoz
Senior Member
544
12-28-2025, 10:25 AM
#6
My thoughts:
This situation is suitable for air cooling and can be adapted again. For quieter operation, front intake fans can be swapped with 140mm models that provide more airflow without noise. Noctua is a solid choice, though it comes at a higher cost.
What is the model of the PSU?
No matter what, after ten years it will likely need replacement.
Purchase only a reliable PSU with a warranty of 7 to 10 years.
An 850w unit could work, but typically a 950w model is slightly more expensive.
RAM prices are quite high. Luckily, RAM often includes a lifetime warranty, making used purchases less risky.
Get just one set of 2 x 32gb drives. It’s best to use the same RAM type, as adding more later isn’t recommended.
Current processors will likely use DDR5 memory.
Consider the Intel Ultra series, maybe the ultra 265K, which is around $290 in the US.
A high-quality twin tower cooler from Thermalright can be both effective and affordable.
If your storage is now an SSD, you can repurpose it.
NVMe M.2 drives perform well in benchmarks, though not significantly better.
M
mcDavoz
12-28-2025, 10:25 AM #6

My thoughts:
This situation is suitable for air cooling and can be adapted again. For quieter operation, front intake fans can be swapped with 140mm models that provide more airflow without noise. Noctua is a solid choice, though it comes at a higher cost.
What is the model of the PSU?
No matter what, after ten years it will likely need replacement.
Purchase only a reliable PSU with a warranty of 7 to 10 years.
An 850w unit could work, but typically a 950w model is slightly more expensive.
RAM prices are quite high. Luckily, RAM often includes a lifetime warranty, making used purchases less risky.
Get just one set of 2 x 32gb drives. It’s best to use the same RAM type, as adding more later isn’t recommended.
Current processors will likely use DDR5 memory.
Consider the Intel Ultra series, maybe the ultra 265K, which is around $290 in the US.
A high-quality twin tower cooler from Thermalright can be both effective and affordable.
If your storage is now an SSD, you can repurpose it.
NVMe M.2 drives perform well in benchmarks, though not significantly better.

Y
YummyGummy_
Member
166
12-28-2025, 10:25 AM
#7
You are looking for DDR5-6000 CL30.
Recommended ASRock B850 Pro motherboards priced at CHF139.-
AMD Ryzen 5 7500F models available for CHF132.-
ID-Cooling FROZN A620 PRO SE CPU coolers at CHF32.70
Western Digital WD Blue SN5000 2TB M.2 PCIe 4.0 NVMe SSD for CHF149.-
MSI MAG A850GL PCIe5 power supply at CHF95.80
Y
YummyGummy_
12-28-2025, 10:25 AM #7

You are looking for DDR5-6000 CL30.
Recommended ASRock B850 Pro motherboards priced at CHF139.-
AMD Ryzen 5 7500F models available for CHF132.-
ID-Cooling FROZN A620 PRO SE CPU coolers at CHF32.70
Western Digital WD Blue SN5000 2TB M.2 PCIe 4.0 NVMe SSD for CHF149.-
MSI MAG A850GL PCIe5 power supply at CHF95.80