looking for a low budget that fits to my a8 6600k

Solution
I basically agree with the GTX1050Ti.

There's no EXACT point at which the CPU becomes a bottleneck since every game varies as to the CPU vs GPU ratio (and it varies within the same game too) but for a BUDGET system a GTX1050Ti is an excellent upgrade.

The CPU part of the APU is almost identical to an FX-4300 so it might be able to run a game like SKYRIM SE at 60FPS (with the GTX1050Ti) at 1920x1080 at mostly high settings.

Again every game varies but I just remember some benchmarks for Skyrim SE.

*I would avoid AMD cards since they never spent the money to optimize their DX11 drivers so there is more CPU overhead.

**Next time please give a BUDGET since the GTX1050Ti is still over $200USD after tax/shipping likely...
I basically agree with the GTX1050Ti.

There's no EXACT point at which the CPU becomes a bottleneck since every game varies as to the CPU vs GPU ratio (and it varies within the same game too) but for a BUDGET system a GTX1050Ti is an excellent upgrade.

The CPU part of the APU is almost identical to an FX-4300 so it might be able to run a game like SKYRIM SE at 60FPS (with the GTX1050Ti) at 1920x1080 at mostly high settings.

Again every game varies but I just remember some benchmarks for Skyrim SE.

*I would avoid AMD cards since they never spent the money to optimize their DX11 drivers so there is more CPU overhead.

**Next time please give a BUDGET since the GTX1050Ti is still over $200USD after tax/shipping likely.
https://pcpartpicker.com/products/video-card/#c=380&sort=price&page=1

I would also recommend at least 8GB of system memory so if you only have 4GB I recommend at least another 4GB (identical in Dual Channel 2x4GB).
 
Solution
Another option is EBay but there's a few problems there:

1) Minimal or no warranty, and
2) card may have problems or die early (some may have been used for CRYPTOMINING and run 24/7 too)
3) older cards lose driver support for newer games first (probably still work but may not be optimal)
4) some cards are FAKE

NOT saying this is fake but it is might suspicious as it's $67USD while it's normal $100 more than that to start?
https://www.ebay.com/itm/GTX1050Ti-4GB-DDR5-HDMI-Graphics-Card-For-NVIDIA-GeForce/153073847613?hash=item23a3e98d3d:m:mRId8LFrgYCvSZuUcNEKj6g&var=452910794973

How is that possible?
 
Update:
I was just glancing around at EBay and noticed THIS:
https://www.ebay.com/itm/GTX-1050Ti-4GB-128Bit-115W-DDR5-PCI-E-2-0-Graphics-Card-DVI-Game-Card-for-NVIDIA/142872776140?hash=item2143e18dcc:g:0Q8AAOSwuehbTwur

What I noticed besides the unknown brand was a "783MHz" GPU?

Also a lot of these cards seem to be missing DisplayPort. I have no idea if they are completely fake or just partially fake. I do know the GPU clock should be somewhere between 1290MHz and 1500MHz for base depending on model.