What is a safe overclock for MSI R9 290X?

[Hero__]

I7 4770 3.4 GHZ
MSI R9 290X 4 GB TWIN FROZER
16 GB RAM
800 WATTS PSU

I would like to know how to overclock the card safely just a little bit for stability (from 1040MHZ to 1080mhz)
I have a msi afterburner however I do not wanna play with my card yet.

 

[chris987]

although reference r9 290x is considered to be running safe at 95c , with your twin frozen cooler i expect a lot better. enything below 85c would be great.!