Hello ladies and gents,
I'm going to show my fan upgrades made to my 620 with pictures, I've tried making it as simple as possible with everything I used. Scroll down if you want to get straight to the CPU cooler change
PART 1: Exhaust Fan

(Ignore the dust please lol, I cleaned it after I was finished) First thing was swapping the exhaust fan, this fan made a lot of noise and to the point of it driving me crazy. I bought a Noctua NF-A9.
Noctua NF-A9 PWM, Premium Quiet Fan, 4-Pin (92mm, Brown) : Amazon.co.uk: Computers & Accessories. This was a fairly easy swap and it's the one thing I didn't have many photos for unfortunately but it isn't too tricky. Unplug the plug you see going from the fan to the motherboard then from what I recall there's another wire to unplug on the opposite end. Just follow the wire from the fan and you'll see the second plug the needs to be removed. The only trick part about this was the plastic keeping the wires managed. I personally just cut the cable management wraps and replaced them with new ones.

Here's the Noctua. It looks a little slanted but that's just the way I was holding the camera. I used the screws that came with the Noctua, if you somehow don't have the screws, the screws from the original fan will work.
So this was my first time ever removing a CPU cooler since this is my first ever gaming PC. I was a little nervous but now that I've did it I realised I was worrying for no reason. It's really easy, though I got help by reading a lot of forums on here. So, first I unscrewed the silver screws completely removing the cooler from the motherboard.

I then cleaned off the thermal paste using Akasa TIM wipes
Akasa TIM Wipes | Thermal Paste Remover | Citrus-based Solvent | 10pcs | Tech for Techs Recommended | AK-TCW-02 | Ideal for CPU, GPU, Heatsink and Chipset : Amazon.co.uk: Computers & Accessories. These wipes worked really well, one was enough for me to remove pretty much all of the paste, then I just used a paper towel just to remove an extra grease.

I then placed these over each of the 4 pins surrounding the CPU. These come with the CPU cooler.

I then attached the bracket that also came with the Noctua cooler using M3x12MM Screws.
sourcing map M3x12mm Flat Head Machine Screws, Phillips Cross Screw, 304 Stainless Steel, Fasteners Bolts 50Pcs : Amazon.co.uk: DIY & Tools. After attaching the two brackets I applied the thermal paste that came with the cooler.
Noctua NT-H1 3.5g, Pro-Grade Thermal Compound Paste (3.5g) : HEINO: Amazon.co.uk: Computers & Accessories. I used the dot method, I used about a pea sized amount of thermal paste.

I then screwed the radiator onto the brackets, you will see in the middle of the bracket where to screw the radiator onto. Screw firmly but obviously don't screw in too hard.

Then clip the fan onto the radiator. I attached the fan so the wire coming out of the fan was facing the motherboard first, but I felt as though it was causing stress on the wire so I switched it to the way it looks here. Also, I was surprised that the fan could fit without my RAM blocking it. Though it doesn't matter for me since I'll be switching to two 16gb sticks next instead of 4 sticks of 8GB.

So, here it is. It all worked! This fan change made a hugeeeeeeee difference for my temperatures and noise. I wish I has screenshots of my temps before and after but I forgot (sorry) but my CPU temperatures went down by a huge 20-25% during most games I play. My next task will be replacing the front fan but that's another task for another day! If anybody sees this, I hope this helped.
[Edited the thread to add issue detail]
FAQ & Answers
MassiveMonkey66 that is a very well explained and documented guide, well done and hope we’ve been of some help to you.
Tinkerer
Tinkerer
Tinkerer
Tinkerer
Tinkerer
PayGOnline
EDIT: HERE is a post about replacing original HSF on PO3-630.
My question is, are you able to adjust the fan speed to this CPU cooler? I tried installing third party software and it does not detect the case fans or even the Noctura fan that we have installed. I read somewhere that acer has some proprietary thing going on in where your fans are not going to be detected in software besides PS. But I do not even have an option to control the cpu fan in PS and I also redownloaded it as well. Is there any way I can adjust this fan curve so I can speed it up a bit or am I going to need to in the near future buy a new MOBO and just move all the parts to that so I am not locked with having to use PS?
I take you have this same cooler as in the pictures above? I'm not sure, but maybe you can slap an additional fan on it. The one in the picture is 25mm in thickness. Noctua has also 15mm ones. If there is enough space on the left... I can't really tell. To get both fans running you would have to use Y-splitter cable that usually comes with the fan.
Thankfully MSI Afterburner can control the GPU fans on 3070.
If you go for a Noctua HSF, you do not need to replace that backplate at all. The bracket that comes with the HSF can be attached to the the original backplate. Just remember to use those "plastic washers" shown in the picture and M3x12 screws.
Tinkerer
What were your thermals before and after the fix?
I have 91°C (195,8 F) on Cyberpunk main menu and 91 while playing Borderlands (from 2009!!!!). This is unacceptable froma gaming pre-buit desktop made specifor gaming.
https://community.acer.com/en/discussion/657469/predator-orion-3000-po3-630-cpu-temp-up-to-91-c-what-to-do#latest
Also, would this liquid cooler be okay too?
https://www.amazon.it/dp/B06WRRDS73/ref=cm_sw_r_wa_apan_glt_i_ATDRV6XEMP8DWR5189DF?psc=1
Thanks
Tinkerer
What were your thermals before and after the fix?
I have 91°C (195,8 F) on Cyberpunk main menu and 91 while playing Borderlands (from 2009!!!!). This is unacceptable from a desktop made specifically for gaming!
https://community.acer.com/en/discussion/657469/predator-orion-3000-po3-630-cpu-temp-up-to-91-c-what-to-do#latest
Thank you!
Thanks in advance!
Did you need to remove those tiny WiFi cables (black and white) from the WiFi card? Sounds like at least one cable might be loose. When the tiny cable is properly connected, you will hear and feel a "click".
Those connectors are so tiny and fragile, in other words pain in the derriere, so be extra careful.
EDIT: Found this while googling "Acer bad wifi". May not help you, but...
"Ok.....I found out what the problem was. It was the Predator Sense smartphone app. When I un-paired Predator Sense from the iPhone app (and deleted said app) my WIFI speeds went back up to what it should be.
This is a shame because it was very useful to control Predator Sense from my phone - not at the expense of WiFi speed though."