The F is going on with my textures

Hey guys, Im pretty new to this so sorry if this is super basic, so basically i have this really nice material that looks pretty decent in the viewport but once i build the scene and lighting (even with production quality) the materials completely lose all quality and look really low res. Ive attached an image to show the before and after.

Thanks in advance for any help or suggestions.

What is the mip map setting for your texture/material?

Your streaming poolsize might have hit its threshold. If you’ve got a capable graphics card you could try using (increasing) the ‘r.Streaming.PoolSize’ console variable. See here:

What Naveed suggested is the correct answer. Increase the r.streaming.poolsize using the console, or adjust its default in its respective .ini file.