I hope ive named these chords right but the look like this


i have trouble playing them (mainly because i dont know how) and especially switching between a "normal" powerchord to one of these two.

Firstly, whats the correct way to play these (fingers used and thumb positions would be helpfull please)

And secondly, any tips on changing between these two power chords to a regular one?
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i'd use fingers 1 and 2, or cover both strings with finger 1.

Its the same finger positioning as Em, just without the rest of the strings

With regards to changing, practice practice practice, over and over again.

I cover both strings with one finger when I play power chords like this.
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Agreed, I use one finger for both chords, my index finger. It takes some practice to get it right. Keep practicing and one day you'll have it nailed.

My buddy fingers them like he's playing minor chords and the higher open strings ring and the chords sound horrible because his index finger isn't muting the unused strings....It's okay to finger them like minor chords, but you must be disciplined when strumming the chords. Good luck and keep practicing!!!
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Jumping on the pile to say that I play both of these with just my index finger. The exception to this is if I were playing an Em chord, which is the same fingering as the first chord you posted except the 4 unfretted strings are played open. For that I use my second and third fingers at the second fret.
Andy Fox
Hard rock guitarist
I play a Jackson DK-2 and an Ibanez RG through a Peavey 6505+ stack
I use my index and middle, so index on top string and middle on bottom, just like an E minor chord. But I tilt my index slightly so it mutes out the other strings. It's hard to get the muting right but it's easier to mute if you're playing in the classical position (thumb on middle of neck not wrapped around) if that's what you're having trouble with.

As for changing to "regular power chords", you just need to practice switching between them. With practice your fingers and mind will get used to the power chord positions so you'll be able to play them without having to waste time making sure your fingers are in the right place.
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LOL I use my Pinky and Ring fingers. Just like if I was playing the 5th and Octave of a regular power chord, but without my Index finger. I don't know if that is right or not.