Shadows causing FPS drop on Radeon 7750

I am having a framerate problem when shadows are turned on.
With the shadows on lowest I get 60+ FPS, but with shadows on low, med, or high I get around 15 FPS!

System Specs:

OS Name Microsoft Windows 7 Professional
Version 6.1.7601 Service Pack 1 Build 7601
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Type x64-based PC
Processor Intel(R) Core(TM) i5-2320 CPU @ 3.00GHz, 3001 Mhz, 4 Core(s), 4 Logical Processor(s)
Installed Physical Memory (RAM) 4.00 GB
Total Physical Memory 3.98 GB
Available Physical Memory 1.79 GB
Total Virtual Memory 7.96 GB
Available Virtual Memory 4.11 GB


Do I have to do something in the Cataltst Control Center?


EDIT: Everything else is set to high!

 

I am sorry, but 7750 isn't exactly a top of the range GPU, it's an entry/medium one. Why don't you just stick to normal shadows or around that?

 

Yes I have the same exact GPU as you and I get 15-20 FPS with everything set to high even shadows but with everything set to low I get 70 FPS with the D-15 Pickup try to overclock your GPU. Mine is overclock with MSI Afterburner Core Clock 650 Memory Clock 921. Hope this helps if you do overclock your GPU watch you GPU temp as if it gets to hot its going to fry itself. Trust me I overclocked it to 931 Memory clock and playing GTA IV it fried it self within a week Do at your on risk

 

On my computer, Q6600, 4GB RAM, Win7 x64, HD7750, I get 35-45 FPS with
- 1440x900 window mode
- everything set to highest except lightning (shadows) low
- post-fx disabled

This is on Dryrock Island with the pickup.

 

Wow, that extremely helped my FPS. Before I turned it off I would get horrible FPS and many FPS drops. After I turned it off it solved all my problems, even on my 9600gt. Thank you so much.