radeon 290x power consumption lower if underclocked?

[vexatious]

Anyone tried underclocking a Radeon 290x to save power? I'm wanting to underclock mine to draw about 180 watts since I can't afford a bigger power supply. I'm thinking I should've gone with a 270x but if I can save power underclocking, maybe a custom bios, I'd be very grateful, especially with the extra shaders and 512-bit memory bus.

Help or suggestions would be great! Thanks!
_________________
Gentoo
Slackware

[Roman_Gruber]

I highly recommend you get a powersupply which enough Watts from a proper brand.

This is total out of scope, the cheap brands do have some written specs but do not meet them. In general a decent power supply from a proper brand will save you lots of hassle. Underclocking will only save you a few percent of power and that will never be enough and it is also not recommended.

[NeddySeagoon]

vexatious,

I'm fairly sure both the binary blob and the radion driver allow you to play with the clock frequency but its aimed at over clockers rather that under clockers
The answer to your question is video driver specific.

Power Supplies are commodity items. You get what you pay for.
At the low cost end, transient performance is poor and gets worse as you get closer to the individual output limits.
At the hight cost end performance improves and you get all sorts of eye candy you don't really need.
Look at cheap PSUs lookat expensive PSUs, then buy something in the middle.

De rating is a good idea too. The PSU runs cooler, which is goood for its life expectancy. As its not working so hard, the transient performance at its actual working load is better.
You can also add extra hardware without embarrising the PSU.

Read the fine print. A 180w PSU (headline value) has restrictions on various combinations of its outputs. Its these restrictions that matter, not the headline power.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.