Extremely slow performance

Hey guys, I have a hackbook with the following specs:

• Dell Vostro 14 5481 (2019).
• i5-8265U with UHD620 graphics, spoofed as UHD630.
• CPU frequency at 1.6GHz with turbo boost up to 3.9GHz.
• MacOS Catalina 10.15.2 installed on SSD NVMe.
• 8Gb of DDR4 RAM, 2400MHz.

My processor is not installed on any original Mac device, but I use the MacBookPro15,2 SMBIOS as it is the most similar to my specs and I've seen on Geekbench the most macOS systems with this processor (which must be hackintoshes) are using this SMBIOS.

However, I felt that performance is not the best it can be - if I use Xcode or OneNote for example which usually tends to take some more resources (depends on the usage of course) the laptop just heats up and things like opening a new project or compiling takes way too long. That also happens on some easier tasks - while the laptop does not heat up, it still takes too long to complete a simple task. for example, compiling a project using theos in terminal (clang + some other stuff) it can take more than 2 minutes which is ridiculous; it shouldn't take more than 20 seconds.

I checked with Intel Power Gadget while doing all of this tasks, and something weird is happening.
whenever it is doing one of the heavier tasks, pkg power goes from 1.5w to 15-20w, and frequency - avg around 1.8-2.0GHz, min on 0.8 (which is idle basically) and max is usually around 2.5GHz and spikes to 3.7 around every 10 seconds or so.
with theos the pkg power goes up to around 10w, and the frequency is behaving the same as when under heavy load.

No matter what I do, at least one the cores are on the lowest frequency and none of them are utilising turbo boost properly; according to Intel Power Gadget at least.

Those are my Geekbench scores versus someone else's similar setup; as you can see, the scores I get are less than a third of his!

What I have tried by now:

• Booting with/without a custom SSDT.
• Boot using CPUS=8 boot flag, and CPUS=4 boot flag.
• With/without VoodooTSCSync, tried the rehabmen's version as well as custom using a tool.
• Tried all combinations with the above options.
• Tried turning HyperThreading off, didn't improve anything.

please help me guys! anything will be appreciated, I don't even know why that happens...