You should not ignore the power .

Bare minimum working is evga 700BR based on 24 amps for 3.3v and 150W COMBINED for 3,3v/5v rails

You need moddiy adapter to use power supply outside the case.

https://www.moddiy.com/products/Dell-OptiPlex-7050-PSU-Main-Power-24%252dPin-to-8%252dPin-Adapter-Cable-%2830cm%29.html

https://www.dell.com/support/manuals/us/en/04/optiplex-7070-desktop/opti7070_mt_service_manual/removing-power-supply-unit-or-psu?guid=guid-e09ec8ac-722e-477a-bcd8-a6fbc4b2f698&lang=en-us

https://www.amazon.com/EVGA-100-BR-0700-K1-Bronze-Power-Supply/dp/B07DTP6MWS

https://www.evga.com/products/product.aspx?pn=100-BR-0700-K1

the combined power required is why the B2 B3 BQ N1 W1 versions from the same vendor do not work. its also why the 600br is not acceptable nor is the 450br etc

SIZE is an issue in the 7070 because the MT is smaller than a real tower.

Cards longer than 8 inches do not fit in the case.

https://www.dell.com/support/home/en-us/product-support/product/optiplex-7070-desktop/docs

https://www.dell.com/support/manuals/us/en/04/optiplex-7070-desktop/opti7070_mt_service_manual/working-on-your-computer?guid=guid-7bf19010-aaf7-4a39-894a-646b3e2f0fc2&lang=en-us

https://www.dell.com/support/manuals/us/en/04/optiplex-7070-desktop/opti7070_mt_service_manual/removing-pcie-expansion-card?guid=guid-da537ceb-fa5f-4355-ba05-b213d2c6abda&lang=en-us

https://www.youtube.com/watch?v=SCQTj1ei3Ew

Graphic card is too weak for this processor:

Intel Core i7-9700 (Clock speed at 115%) with NVIDIA GeForce RTX 2060 (Clock speed at 100%) x1 will produce 15.83% of bottleneck. Everything over 10% is considered as bottleneck.

Graphic card and processor will work great together

Intel Core i7-9700 (Clock speed at 100%) with NVIDIA GeForce GTX 1660 Ti (Mobile) (Clock speed at 100%) x2 will produce only 1.13% of bottleneck.  The catch?  I still don't know what "mobile" is supposed to mean.  At least 32GB RAM is recommended.

Graphic card is too weak for this processor:

Intel Core i7-9700 (Clock speed at 100%) with NVIDIA GeForce GTX 1660 (Clock speed at 100%) x1 will produce 23.31% of bottleneck. Everything over 10% is considered as bottleneck.  We recommend you to replace NVIDIA GeForce GTX 1660 with NVIDIA GeForce GTX 1080 Ti.

Graphic card and processor will work great together:

Intel Core i7-9700 (Clock speed at 105%) with NVIDIA GeForce GTX 1080 Ti (Clock speed at 115%) x1 will produce only 0.21% of bottleneck.  At least 32GB RAM is recommended.

The above quotes come from PC Builds.  I couldn't it to pull up the GTX 1660 Super.

As for the GPU's with the least amount of bottleneck, of course, this is granted the PSU is upgraded as speedstep suggested.  As long as one is comfortable with PSU outside the case.

Images will appear when approvered by moderation:

 NVIDIA GeForce GTX 1080 Ti is not ever fitting into 7070 case.

thats bad advice

 1080 ti used in video was installed into xps400 from 2006.

1080 ti needs 850W power supply.

1080 in video is in 2006 xps 400 tower

https://www.youtube.com/watch?v=qa9b0TkTsLM

12 inch card

@speedstep,  Saying "That's bad advice," usually in big red letters, whenever you disagree with someone is callous.  You still can't make corrections without it.

Yes, @speedstep, whenever you know something somebody else didn't, you always handle it so well.  I didn't say I wasn't wrong.  I see your response came in while I was typing another reply.

There's a difference between saying "That's bad advice" and "Did you know...?

You've gotten numbers wrong before.  Instead of saying "That's bad advice" in bold letters, I simply made the correction, sometimes with a screengrab from a manual or other source.

What speedstep did right is a 12 in. card won't fit.  There's a 267mm version of it which is shorter, but that's still 10.5".  As speedstep said, 8" is the max to fit in a 7070.

Speedstep and I probably won't agree on PSU's.  Nvidia and GeForce recommend 600w PSU's; screengrabs below.  Speedstep normally recommends 750w PSU's so there's enough power on the 3.3v/5v rails.  I get that.  However, I wasn't expecting a recommendation of 850w.

Some good news...  You already have a great CPU with UHD graphics.  Intel's UHD Graphics 630 IGP operating at 350 MHz with a burst frequency of 1.2 GHz.

I use red to indicate negative and always use big letters.

Telling someone a 12 inch 3 fan card is recommended when no such thing works or physically fits into the case is bad advice.  Complaining that its not bad advice doesnt change the fact that both the power supply and the physical size of the card prevent 1080TI from EVER being used.

Callus is telling people they can buy a $700 video card that they will find does not fit at all in the case and the power supply does not work at all for.

1080 ti needs 850W power supply

https://www.dell.com/support/manuals/us/en/04/optiplex-7070-desktop/opti7070_mt_setup_specs/set-up-your-computer?guid=guid-2d17bb7f-0cad-4468-b7ac-492c800696fc&lang=en-us

https://www.dell.com/support/manuals/us/en/04/optiplex-7070-desktop/opti7070_mt_setup_specs/back-view?guid=guid-40f421e9-26e3-4a8e-9835-11df1fbc2e56&lang=en-us

850w is based on current DELL power supply model used in systems that have a 1080TI which you recommended Brad.

There are 850W units that are not to Dell spec based on the EPS12V and the 3.3V/5V combined power spec.

DELL 460W unit has more power on 3.3V/5V rails than 850w SEASONIC.

All rails count.  POWER SUPPLIES are not a single spec of WATTS.

Note 3.3v goes UP to 30 AMPS and 5v GOES UP to 32 AMPS 160W with combined power of 225W for that rail set on the Dell 875W unit used in Alienware and Precision Models that support the 1080TI.

W299G 875w Delta

W299G uses specific WIRING HARNESS R166H

Dell N1WJD 48Y6D Alienware Aurora R5 R6 Model Numbers: D850EF-00, DPS-850AB-2A, 0N1WJD, 048Y6D

N1WJD is modular so it uses many cables not a single wiring harness like the 875 used.

dell 875 30AMPS 3.3v 32AMPS 5v

CHANGES TO EPS12V and 3.3V/5Vdell 460 VS SEASONIC 850

"There's a difference between saying "That's bad advice" and "Did you know...?"

The passive aggressive rarely takes responsibility for giving incorrect bad advice. Requiring me to Validate something is correct when its ALWAYS wrong is playing the victim. I am not accountable for your choices nor should I be.

It changes nothing. Telling someone a $700 card that will never fit in the case is bad advice.

This has not changed.

Telling someone that a card that requires 850W power supply is recommended when the unit has 260W power supply standard and no option for a larger one is bad advice.

This has not changed.

Recommendation of the GTX 1080 ti was retracted when I also said it wouldn't fit.  Lord speedy failed to see that and notice I said he was right about the length.