I just bought a NZXT c850 and it's working perfectly, the problem is with the EVGA 750 GA , hopefully they can help me with it changing it or something, I bought the evga new as well just for the 3080.

I am also having this issue and I’m incredibly frustrated. I bought a brand new 850W GA about 2 weeks before my 3080 FTW Ultra to make sure I was all set. If I raise my power limits on X1 I start to experience crashes. Even with no OC, Raising power limit and trying to run an OC Scan causes my system to crash and reboot. This is on a 7700k, and there is no way this setup shouldn’t work. Now it seems to be a confirmed issue, and based on that response someone here got, there no plan or way to fix it?

I've tried several fixes before just making my decision to purchase a new PSU, I bought a GA Model for the 3080 as well and is extremely frustrating that it doesn't work, I got a C850 from NZXT and it's working perfectly, not a single issue.

rancel21342
I am also having this issue and I’m incredibly frustrated. I bought a brand new 850W GA about 2 weeks before my 3080 FTW Ultra to make sure I was all set. If I raise my power limits on X1 I start to experience crashes. Even with no OC, Raising power limit and trying to run an OC Scan causes my system to crash and reboot. This is on a 7700k, and there is no way this setup shouldn’t work. Now it seems to be a confirmed issue, and based on that response someone here got, there no plan or way to fix it?

Have you contacted EVGA support about this issue?  They will want to know your configuration but I'm assuming your setup is well within the "normal" limits of an 850 watt PSU.  It clearly isn't working so I hope they will help you out.
They should probably pull this line from their product page and wattage calculator until this gets sorted out.  Right now if you plug in a 10900K with a RTX 3090 it tells you the 750 GA is a good option.

nrmazloo

rancel21342
I am also having this issue and I’m incredibly frustrated. I bought a brand new 850W GA about 2 weeks before my 3080 FTW Ultra to make sure I was all set. If I raise my power limits on X1 I start to experience crashes. Even with no OC, Raising power limit and trying to run an OC Scan causes my system to crash and reboot. This is on a 7700k, and there is no way this setup shouldn’t work. Now it seems to be a confirmed issue, and based on that response someone here got, there no plan or way to fix it?

Have you contacted EVGA support about this issue?  They will want to know your configuration but I'm assuming your setup is well within the "normal" limits of an 850 watt PSU.  It clearly isn't working so I hope they will help you out.
They should probably pull this line from their product page and wattage calculator until this gets sorted out.  Right now if you plug in a 10900K with a RTX 3090 it tells you the 750 GA is a good option.

Yup it does tell you it’s an option and clearly isn’t. Bought it from Newegg at end of September, have no option to return. I did open a ticket today at EVGA but based on what I’m seeing from others their gonna nicely tell me that it’s a low end psu and nothing they can do. I emailed them about some coil wine when I first got it, and they sent me an email saying it was “an entry level psu”. Okay, so what? It should still be able to run this card with the rating it has.

Not sure what I do next. I could just say hell with it and buy a 1000w G5 and make sure I’m good for a long while. Was planning to get a new AMD chip after launch and if it can’t run a 7700k that’s obviously not going to work.

Ideally EVGA would let me send it back and swap to a different psu, but since I bought it from Newegg I don’t see that as being an option. And Newegg won’t take it back either so guess I own it.

I'm in the exact same boat. Just got my 3080 today and spent 3 hours trying to get it to post. I swapped where the 8 pins plug into the power supply and it worked...for 10 minutes. Once I was in windows and installed the drivers, i got a black screen. Had to wait a bit to get back into windows. Actually managed to try horizon zero dawn and as soon as I quit...blank screen. At this point I am just gonna go get a power supply locally. I'm done waiting.

I am having the same issue. when I run stress tests, the entire computer will power down. Using MSI afterburner and other monitoring software, there is no heating issues as the CPU will cap at about 60 even when at full load due to custom loop, and the GPU never gets over 70.
My current settup is 
CPU= AMD Ryzen 7 3700x
GPU= Nvidia 3080 FE
MOBO= MPG X570 Gaming Pro Carbon Wifi
Ram= G.Skill Trident Z RBG 16GBx4
PSU= EVGA Supernova 850 GA
CPU Cooling= Custom EK Res and Loop
Fans= 4 corsair RGB's & 6 Noctoa's
Case= Lian Li 011 Dynamic XL
 
The temperatures run completely fine, so it isn't a thermal shutdown. The issue continually repeated itself when launching War Thunder at max settings. Also several benchmarks such Like 3D Mark occasionally repeat the process as well. I replaced the PSU with a corsair 850W 3 days ago and have not been able to replicate the issue. I fully believe that this PSU just isn't working well with the fluctuations of this poorly designed GPU. 

Just wanted to add that I too just bought an EVGA Supernova GA 850W power supply for my latest build, expecting it would be fine with a 3080, only to find that it is clearly not.
 
PC Parts:

• EVGA Supernova GA 850W (of course)
• Gigabyte Aorus Z490 Ultra
• Intel 10700K CPU (overclocked +200 MHz all cores, max clock 5.3GHz, probably not helping power situation)
• Crucial Ballistix 3600MHz RAM, 2x16 GB
• EVGA 3080 FTW3 Ultra, stock clock

 
Other accessories being powered:

• NZXT X53 Kraken AIO, with 2 NZXT fans
• 6x Corsair ML120 case fans
• 2x SSDs (SATA)
• 3x NVMe disks

 
Fortunately for me, we are working on another computer for someone with a much less demanding setup, so my Supernova PSU will just get transferred as soon as my Corsair HX1200 replacement arrives (Sorry EVGA, I'll remain loyal to your graphics cards and your service for the foreseeable future, but this is not a good first impression of power supplies... I miss PC Power and Cooling, but I digress).
 
UPDATE 2020-11-06:  The Corsair HX1200 tests fine but is DOA when you try to power even a basic computer with it. Looking at recent reviews, this appears to be very common recently. I guess Corsair is off the list, too.
I put my 12-year-old PC Power and Cooling 850W PSU in here with the 10700K and the 3080 FTW Ultra and so far, no problems.
 
UPDATE 2020-11-10: So far the old PC Power & Cooling 850W unit is holding strong. Metro Exodus plays with RTX and other settings all on Ultra, DLSS *disabled*, at 100+ FPS without suddenly turning off. I am currently pretty happy with the setup.

Pretty sure the 850GA is an Andyson unit  , I have read a lot of not so great things about Andyson units in general. But, the good thing is EVGA will most likely take care of you with their excellent support.

I have same set up did that new power supply work?