how to remove nvcpl.dll startup.

you could try replacing and re-registering the file yourself. I would do it like so:

1. Unregister the DLL
Go to Start -> Run
regsvr32 -u NvCpl.dll

You should get a message saying the DLL was unregistered.

2. Replace the DLL file.
Find another computer with nvidia display drivers installed, and copy NvCpl.dll from it's system32 directory.
Backup your existing DLL by finding it in C:\Windows\System32\ and renaming it to NvCpl.dll_backup
download and Copy new DLL into your system32 directory, where your previous one was.
Download nvcpl.dll

3. Register the DLL again
Start -> Run
regsvr32 NvCpl.dll

You should get a message saying the file has been registered again.

Restart, and see what happens.