Minecraft Shaders lag for no reason?

I used to get over 100 fps when using any Shader pack, last night however i only top getting 25 fps when using the Shaders. I have no idea why it changed but it used to be fine. I can play any other game maxed out to date.

My GPU is GTX 780
My CPU is i7 4770K
16Gb Ram

Added (1). i also used optifine

Mitch

The i7-4770K has an integrated video card, have you checked if you didn't accidentally set that to standard for javaw.exe?

Luuk