Safe GPU clock, memory and temperature for GTX 970?

[cowtato]

Intel - Core i7-4790K 4.0GHz
Cooler Master - Hyper 212 EVO
MSI - Z97-GAMING 5 ATX LGA1150
G.Skill - Sniper Series 16GB (2 x 8GB) DDR3-1866
MSI - GeForce GTX 970 4GB Twin Frozr V
EVGA - SuperNOVA P2 750W 80+ Platinum
Asus - VP247H-P 23.6" 1920x1080 60Hz Monitor

What would be a safe bet to overclock my graphic card without reducing its lifespan? Thanks

 

[Airex]

Shoot for 1450mhz (can get higher, test it) on the gpu and +300mhz (not really worth spending a lot of time) on memory. I would use msi afterburner and go slow in 10mhz increments as you get closer to the target. Don't go higher then 80c for extended periods if you really want your card to last. It can however handle 90c if it really needs to.