Mass Effect Legendary edition poor perfomance

Since you mentioned that your PC didn't had problems until you switched out then it might be the the PC. There are a masterful of PC gamers here that would surely aid you but just in case, check the pinned post containing MOD that can be of help, but this might be the platform.

@EA_Mako do you know any high speed PC user?

@prophetarmaggen 

Please create a DxDiag in text file format and post it with your next reply. You can do that  with the "Choose file" button at the bottom right corner of the reply window. 

I did what you said,step by step.

@prophetarmaggen Do you have any overlays turned on? (AMD overlay, Steam, Origin, Discord, etcetera?)  I have found these to be huge contributors to bad FPS in many games, and I usually disable almost all of them.

Also are you using the Steam version or Origin version?

I use Origin,tried to disable Origin overlay,but no changes,still i didnt try to disable AMD overlay.

@prophetarmaggen 

There are some rather unusual errors regarding the NetworkDiagnosticsFramework of Windows.

It is hard to say if that plays a role here, but it can't be ruled out.

Apart from that, one of your drives has the drive letter :B, as far as I know Windows still can't index a drive with A: or B: drive letters.

But that should not play a role in regards to a direct access scenario as with loading a game. 

In general, there are places in LE1 that have general performance problems, like parts of the Citadel and uncharted worlds.

You should not test with LE1 in general.

Please preform a clean boot and test the game in clean boot mode.

Make sure your virus scanner and other security software and also Afterburner and similar software is disabled.

Make also sure that your GPU & CPU are not overclocked.