I've been noticing a few disturbing trends on this thread.
- asking whats a "safe" OC for their model.
- asking to have OC FW spoon-fed to you
First, there is no "safe" overclock. The closest thing is the 600/750. Start there and increment up slowly, being careful to looks for signs of instability. If we said, 650/900 is "safe" for most 40nm GPUs, that might work 9/10 times, but that one person will be SOL and kicking themselves for not taking a more cautious approach.
If you are not willing to be cautious and are looking for a quick "safe" OC to boost performance, stick with the 600/750. If you go higher, prepare for it.
In order to do that you will need the FW, which you can build yourself using MFW builder. You can learn how here, by sesrching and reading the thread.
I understand the desire to simply ask, but consider that we have to find the post to direct you to. You are shifting the burden of searching onto someone else. Asking them to upload a FW for you, when it may have been uploaded already, or you could generate it yourself for any OC combination you like.
Overclocking is experimental and as such it should not be undsrtaken lightly. We should not encourage wreakless attempts by providing advice to jump strait to a high OC, or fulfill endless requests for new FW combinations.
If they are determined enough to do it, they arguably should put in some research effort. The info is here.