I feel like they're a little higher than normal. My i7-4790k is cooled by an H100i with stock speeds at about 36-40C on idle. My R9 290x Twin Frozr runs at 40-48C on idle, but for some reason goes a bit above 50C while watching videos? These are pretty new, so I don't think it's the dust. Ambient temperature is at around 28-30C