Windows .exe Having lag issues with FTB...

[MasterFSK]

... but normal Minecraft is running completely fine.

Greetings people of the FTB forums!
This is actually not my personal problem, but my friends problem, and we can't seem to find out the source of the problem.
When we look at the processes running, the machine ain't even using any resources to run the game at all. He says the processor is utilizing about 20-30% of it's capacity while running FTB.

So since neither of us is particularly knowledgeable in this subject, we have to ask people for help.

I've listed a summary from the program "System Spec" to see if this can shed some light over anything.

Spoiler

Item Details

Windows: Windows 7 Home Premium Edition (64-bit) Service Pack 1 (Build 7601)
Memory (RAM): 12181 MB
CPU Info: Intel(R) Core(TM) i7-3630QM CPU @ 2.40GHz
CPU Speed: 2393,0 MHz
Sound Card: Speakers (2- G510 Gaming Keyboa |
Realtek Digital Output (Realtek |
Speakers (Realtek High Definiti |
Display Adapters: Intel(R) HD Graphics 4000 | Intel(R) HD Graphics 4000 | Intel(R) HD Graphics 4000 | NVIDIA GeForce GTX 660M | RDPDD Chained DD | RDP Encoder Mirror Driver | RDP Reflector Display Driver
Monitors: 1x; Generic PnP Monitor | Generic PnP Monitor | Generic PnP Monitor |
Screen Resolution: 1920 X 1080 - 32 bit
Hard Disks: C: 111,4GB | D: 698,6GB
Hard Disks - Free: C: 43,0GB | D: 419,1GB
Motherboard *: CLEVO CO. W3x0ET
IP Address:
SM BIOS: 4.6.5

He have deleted & re-installed Java countless times, and making sure it's up to date.

What amazes me in particular is that it works perfectly on vanilla Minecraft though...
If anyone familiar with this problem have a solution or need more info, please do respond.
It's getting quite annoying for the both of us.

Yours sincerely,
MasterFSK

 

[Runis]

Are these FPS or network lag issues? If it's network, you could try an `ipconfig /flushdns` in cmd prmpt. Beyond that, try resetting the router or other methods that you could Google around for.

If it's FPS:

Your processor is an i7. I didn't bother looking if it's quad or dual core, but most i7s are quad-core. At that, i7 has two logical processes per core. This results in essentially eight logical threads. MineCraft can only comprehend the usage of one logical thread. With Optifine, it allows you to use two logical threads (this is a huge issue for me since I kind of have more than logical threads - and therefore - do not use near as much power as I could). You did not mention that your friend has Optifine. If they don't, I recommend downloading it and using this thread on the FTB forums to help you install it. It greatly helps with FPS. Check the Video Settings to mess around with the video.

If your friend is using a high-res texture pack, that is most likely the issue. Texture packs such as 256^2 and 512^2 are quite taxing.

 

[MasterFSK]

Thank you for the reply!
We have tried Optifine, and no change at all actually.
He's using vanilla textures as a matter of fact.