My minecraft is glitching?

My minecraft keeps glitching so where the blocks change to invisible blocks or other random blocks. This happens while I'm using the Faithful32x32 resource pack and TheHunterWolf Pvp pack. (These are the only two I've tried) Today I just deleted my minecraft folder and installed Forge Modloader 1.6.4, Pixelmon 3.0.4, and Optifine 1.7.4. Before today, I've never had this problem. My gamma is set to 1000000.0, and I'm trying to play on us.mcgamer.net

Which PC is better for gaming and overall performance?

http://www.thesource.ca/estore/product.aspx?language=en-CA&product=8009200&category=Desktops_English&catalog=Online&tab=2#more

http://ca.gateway.com/gw/en/CA/content/model/DT.GEJAA.001 Computer store selling it for $489

Don't suggest any other model or to build my own please.

Which one will run GTA IV, Minecraft, and Dayz better? Which is less likely to lag on the internet and which one is better bang for your buck.

Added (1). I also should ask if the first one from the source has a dedicated GPU or not? I know the second doesn't

Minecraft low fps on a new computer?

Prossesor - AMD FX-6300 Vishera 6-Core 3.5GHz (4.1GHz Turbo) Socket AM3+ 95W Desktop Processor FD6300WMHKBOX

Graphics Card - MSI R7 265 2GD5 OC

ram - 8GB ddr3

What is the best gaming computer?

Right now i have a windows 8 pc with 8 RAM. Though while trying to play minecraft and running shaders it only gives me around 14-25 FPS. I just want a good, fast running computer that is great for minecraft. Specifically shaders.

I'm trying to run shaders on my minecraft but i'm getting a low FPS?

I know shaders may cost alot of lag, but its causing 14-25 FPS on my minecraft using LITE.
I have a windows 8 laptop that i got for christmas. So its still pretty new.

Intel(R) Core(TM) i7-4700 MQCPU @ 2.40GHz

8.00 RAM

64-bit operating system, x64-based proccessor

Minecraft some maps don't work?

My family are sharing minecraft and my sisters maps keep crashing.
we lode the map and it starts to load and then crash. And some time it will load in the middle of her playing and she will lose all her progress.

and one map I made yesterday crashed in the middle of my play.

some maps we made are new. But some we have had for weeks. (they did work before)

it started about a week back.

Added (1). We have had the game for about a month.

Help my ping fluctuates when I'm in games?

So first off I'm going to say that I'm on OSX with a wireless connection. As well I went on a 2 week vacation, before the vacation all was fine, then the second I got back on my ping went crazy. So when I play games, such as League of Legends, minecraft, and CoD, about every 10 seconds my ping will jump really high. I have tried some things suggested already on the web but none of those helped. It is very annoying.