as soon as i start the downloader, my graphics card goes from 135 to 1215 mhz... Has anone else noticed this?

My GPU clock spikes for a moment when starting the downloader, then goes back to idle speed immediately. Are you sure nothing else running is causing this, a web browser using hardware acceleration can do that.

Nah it only happens, as soon as i start the downloader. The card spikes and remains there

Same here. I opened the Downloader and started downloading with GPU-Z on and the clock sensor blinks and, even if it does not increase the value, the graph show some puntual spikes if you keep looking at it.
ATI HD 7870, not OC.
Weird issue.

EDIT: Removed what i posted before.

My clocks spike when I open anything on my machine, then goes back to idle speeds shortly after. Not sure what's up with it not returning back to idle on your machines.

Weird... Do you test it on different computers or not?

Just on this one. With two different craphics cards though.

According to your post and other users' comments, it needs developers' attention. Contact them. Maybe it's a common issue and needs to be fixed in the future releases.

I have the same issue with the single core cpu at my desktop pc - it spikes to 100% cpu usage and stays there till the download ends - very frustrating :(. Haven't tried it yet on my laptop which is far better than my desktop.