Vega 56 settings and help

Hi , i just installed my new gigabyte vega 56 oc card.
i am running cpu i7- 7700 , pb 500w psu , 16 gig ram ,
I had a go at increasing the power limit , and then undervolting .
I ran some tests with fur mark and time spy etc and sometimes it crashed.
I also got what i think was thermal throttling , but i think it might be my cpu , as even if i set gpu to turbo not custom , it locks up before my gpu fans kick in.
So have i got enough power to run this card?
And if not if i undervolt will it help?
Also there are so many preset setting im confussed as to which to use .
There is in amd settings ,powersave ,balanced,turbo etc, and then within custom there is auto overclock, auto undervolt etc.
First of all i need to work out if my system will run this card on custom, and if it will what custom settings do i use ? , and if not what auto setttings do i choose?
thanks mark

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Also i just ran a benchmark on shadow of the tombraider on my 1440 monitor and got 61fps on highest settings, but on world of warcraft it crashes.
Update , after running that benchmark my pc froze ,

Radeon™ RX VEGA 56 8G | Graphics Card - GIGABYTE Global
System power supply requirement: 650W

and usually when they say that try to go a step or two more i.e 700 / 800W since they do the measurement on power efficient systems .

the rest of your thread is you trying vaguely to destroy your cpu for no reason by trying to utilize overclocking and underclocking at the same time , why are you trying to do so ? is this the first time you own a dedicated GPU ? btw GPU's almost do it all when it comes to games , the computing part hardly hits the 35% CPU utilization mark so i suggest you stop tinkering with your CPU before you break it .

Are you trying to overclock a processor that has a locked multiplier?

Hi , i will order a new power supply tomorrow.
I have for now put my gtx 1060 3gig back in.
And yes i am inexperienced the vega would be my first high powered and also amd gpu .
I didnt change the cpu settings at all , was just following things on the vega 56 i have watched/read .
I couldnt work out why it was crashing.
Once i get this power supply and put the vega 56 in , should i just leave it on standard settings ?

if these are extra over clocking tweaks for the gpu i suggest you reset them back all to default and wait till you have your new high power psu .

the over clocking options are usually made for "modders" as cooling system provided (a fan or two or a heat sink or whatever) is usually optimum for normal use , additional tweaks may produce extra heat that if not handled by improving or exchanging current cooling system by another may result in crashing and instabilities . sometimes the card's cooling system can allow for marginal tweaks , and in such case overclockers start by fractional increase in voltage/gpu Mhz speed/memory bus speed and wait to see if system continue to running stable before stepping up again until the reach optimum most stable configuration the system can handle , in all cases this buys you 2~5 extra frames so why the bother.