Question PC accessing drives very slowly randomly. It makes it hang and freeze.

[Albertinio]

My computer has a primary SSD and a secondary HDD.
It started hanging when trying to access my secondary HDD where windows is not installed. I've had problems where HDDs have died before, so I tried replacing it (twice), so a failing HDD is pretty much out of the question. RAID and CHKDSK all said my HDDs were fine.
So I tried replacing my PSU in case it was faulty and maybe not supplying enough energy for the disks to spin properly, but it didn't work either.
And now, I've somehow managed to detect my PC failing to access the main SSD. I used a bootable Ubuntu USB and the responses were slow too, so it's probably not Windows failing. The way I detected the particular way the access time was slow was using the "benchmark partition" from the gnome disks utility: when it goes normally, it accesses the drive up to 100 times to check writing and reading speed and all data points are close to each other. However, when accessing my drives, even the new ones, it randomly drops to zero speed for unknown reasons and it stops performing the benchmark for a while.
Is it possible for my CPU to be failing? Or is it the motherboard? I've tried replacing the cables and swapped the position of the drives to check if that's the cause of the issue but to no avail.
Pictures of the benchmarks using hdtunepro:
SSD
View: https://i.stack.imgur.com/tUmnT.jpg

HDD
View: https://i.stack.imgur.com/uZfuk.png

Computer specs:
CPU: AMD Ryzen 3 3100 3.6GHz
Motherboard: B450M PRO-VDH MAX (MS-7A38)
GPU: AMD RX 5500 XT 8GB
SSD: Kingston 500 GB
HDD: Seagate Barracuda 2TB
PSU: Cooler Master MasterWatt 650 EU

 

[Albertinio]

I think your getting close to swapping parts.

Just for a test unplug the hdd see if anything changes.

Test each stick of ram in the proper slot one stick at a time.

Unplugged the HDD, SSD is still acting up. Gonna try the memory thing.

Thing is, I don't know what to replace since the drives are supposedly fine (and the hdd has been replaced twice in 2 days). I already ordered a motherboard, but it could also be my CPU. It's baffling to me why this is happening.

 

[Albertinio]

I think your getting close to swapping parts.

Just for a test unplug the hdd see if anything changes.

Test each stick of ram in the proper slot one stick at a time.

Tested each stick of memory on their own, both are working fine. SSD still spiking.

 

[Albertinio]

I think your getting close to swapping parts.

Just for a test unplug the hdd see if anything changes.

Test each stick of ram in the proper slot one stick at a time.

I replaced the motherboard and tested another SSD, no success so far. My only and final guess is the CPU but that doesn't make sense to me...

 

[mdd1963]

DIsconnect the spinning drive, and test using just the SSD. I've seen problematic spinning drives cause extreme sluggishness in PC operation, such that when the drive was even connected (even after quick formatting), even after the entire PC took a long time to boot, open apps that were resident on the NVME drive, etc...

A failing drive can play absolute havoc with a system, and not really throw any errors indicating the drive is failing. (My only real hint was that the spinning drive took 20 seconds to even quick format, which is normally a 2-3 second affair at best)

 

[Albertinio]

DIsconnect the spinning drive, and test using just the SSD. I've seen problematic spinning drives cause extreme sluggishness in PC operation, such that when the drive was even connected (even after quick formatting), even after the entire PC took a long time to boot, open apps that were resident on the NVME drive, etc...

A failing drive can play absolute havoc with a system, and not really throw any errors indicating the drive is failing. (My only real hint was that the spinning drive took 20 seconds to even quick format, which is normally a 2-3 second affair at best)

I've tried that too. I still don't know what's happening, but it's still having the same issues.