MP 1,1-5,1 Mac Pro painfully slow after firmware upgrade 4,1 to 5,1

[ccrivia13]

I’ve successfully upgraded the firmware on my 4,1 Mac Pro to a 5,1 (now officially running High Sierra). Everything worked perfectly fine until I enabled SIP again. Now everything runs painfully slow, just opening Launchpad for example takes what feels like ages. Also, if I want to open apps they just crash immediately.
For some reason all this started happening after disabling SIP. Can anyone tell me how to fix this issue? Right now my Mac is pretty unusable..

Edit: I feel like it could be the graphics card, since my Finder window for example ‘multiplies’ when dragging, there are also some weird artifacts. Yet I have the latest drivers installed, and like I said, before re-enabling SIP everything worked perfectly fine..

 

[tsialex]

I’ve successfully upgraded the firmware on my 4,1 Mac Pro to a 5,1 (now officially running High Sierra). Everything worked perfectly fine until I enabled SIP again. Now everything runs painfully slow, just opening Launchpad for example takes what feels like ages. Also, if I want to open apps they just crash immediately.
For some reason all this started happening after disabling SIP. Can anyone tell me how to fix this issue? Right now my Mac is pretty unusable..

Edit: I feel like it could be the graphics card, since my Finder window for example ‘multiplies’ when dragging, there are also some weird artifacts. Yet I have the latest drivers installed, and like I said, before re-enabling SIP everything worked perfectly fine..

This is weird, the only know way that the BootROM can cause GPU problems is when you have a rare combination of MP4,1>5,1 + NVIDIA TITAN + NVIDIA web drivers.

If it's not your exact combo, look elsewhere.

 

[ccrivia13]

This is weird, the only know way that the BootROM can cause GPU problems is when you have a rare combination of MP4,1>5,1 + NVIDIA TITAN + NVIDIA web drivers.

If it's not your exact combo, look elsewhere.

Currently I have my old GTX 750ti in my Mac with the current Nvidia web driver.

 

[ccrivia13]

This is weird, the only know way that the BootROM can cause GPU problems is when you have a rare combination of MP4,1>5,1 + NVIDIA TITAN + NVIDIA web drivers.

If it's not your exact combo, look elsewhere.

Reinstalling High Sierra solved the issue with my Mac being extremely slow.

Now, I still can't open ANY AppStore application.
I looked into the error message:

Exception Type: EXC_CRASH (Code Signature Invalid)
Termination Reason: Namespace CODESIGNING, Code 0x1

I have no idea how to solve this and couldn't find any solution to it.
I hope going back to 4,1 will solve the issue.