Hello, so my friend recently built his own PC. It has an i3 2100, an ACER H61H2-AD motherboard with 8 GB of CL9 1333MHz RAM. He currently doesn't have a dedicated graphics card, and minecraft vanilla runs at 80-100 FPS on lowest graphics settings, with GPU usage hovering at around 14% in MSI Afterburner. When he loads some mods (around 70, his cpu and ram should be able to handle them) his FPS drops to 2-3 FPS while looking forward, around 80 while looking up and 12 while looking down. His CPU usage is around 60% and only 5GB of RAM are used. GPU usage stays the same, so I've been wondering what causes all that lag.