I have been experiencing a visual glitch on Hexxit for a couple of days. It started when I was in my friends private server and he spawned a dungeon in the twilight, this was after playing the modpack for two days or so. It only happened that one time, but we have now moved to a public Hexxit server where this glitch comes about every 10 minutes or so and makes the game unplayable. If I am in an area by myself the glitch does not seem to happen, but after someone starts placing or destroying blocks the glitch happens after a random amount of time.
I use a laptop with these specs
Centrino Duo 1.66GHz Dual Core
Intel 945GM express integrated Chipset
Windows XP SP3
My video card does not support Open GL
I have the latest versions of java and graphics card drivers. My computer can run minecraft fine with all settings on the lowest as well as Hexxit before this first happened. Changing to a different texture pack does solve the problem for a short amount of time. This glitch happens with and without optifine installed, which is the only other mod beyond the basic mod pack.
This is me looking at a 2x4 dirt wall up against the cobblestone bricks. You can see how the blocks are outlined by the cursor but otherwise invisible.
Here I have dug a 1x2 hole into the ground and jumped into it
Its to be noted I can interact with invisible blocks, both put down or destroyed by me or someone else. While breaking one I can see the chipping animation along with the sounds as well.
Thanks for any help or consideration