Not sure if this is the right place to ask but I have a doubt.
I was mounting a new rig. Initially it used just a rx 570 8gb: worked fine. Then I added a rx 480 8gb through one of those pci express usb adapters that turn x1 slots into x16 ones.
At first both gpus stopped working altogether, windows was giving code 43 (even when i plugged them individually). Did some trouble shooting and found the issue was probably windows installing conflicting drivers; reverted both of these card's bios to the original one then did a DDU and they started working fine again.

However, now when plugging on the same rig again (one on the x16 slot and the other on the x1 slot through an adapter) the one plugged through the adapter is extremely unstable. MSI afterburner shows its values oscilating like crazy at idle, the pc keeps freezing slightly every 5 seconds and the fans also stop spinning randomly. Impossible to use it like this.

Both cards are on their original bios, haven't flashed back to the modded yet since I wanted to test first. And from my estimations the psu should be enough: It's a 550 corsair and hwinfo64 tells me these cards only draw 100w each while at heavy load. At the very least the psu should be enough to keep stable in idle.
Plus, the fact only the card on the pci express adapter is causing problems tells me the problem is the adapter itself.
 
Anyone know what could be it? Or anyone with experience using those adapters suffered something similar? It's that one with blue slot and blue USB cable.
Would appreciate any help.

How much are you guys making with 30 ethash in recent days?
Whattmine is saying high values, like $4,5, yet I can only get around $3,6 per day per 30 ethash.
I realize mining calculators are not perfect but the difference being so off is making me curious if others are making more.

I did use polaris to flash the bios; copied ''777000000000000022CC1C00AD615C41C0590E152ECC8608006007000B031420FA8900A00300000 010122F3FBA354019'' timing strap to 1750 and 2000.
Tried to use the ''one time click patch'' at first, but after flashing the pc would crash during stress testing so I rolled back. My uneducated guess on the cause for that is since the editor recognized two memories, samsung and hynix, despite my card being samsung, that made the automated strapping edit both, which caused some sort of error. With this in mind I edited only the samsung straps and this time it endured stress testing. However, I'm not getting the performance expected, making me think I did something wrong again.

As for increasing memory, that's another thing. Before flashing I messed with overclocking and undervolting a little and recall being able to get somewhat stable performance at 2150 memory. Now I can't rise it above 2000 without getting hundreds of memory errors. At 2150 I get artifacts even.
Granted, I didn't check for memory errors on the previous overclocks, but the PC gave no signs of being stressed.

Do you think I should roll the bios back and try another flashing? And any suggestion on how I should go about it?

Some pics for reference:
GPU-Z (post flash) : http://gpuz.techpowerup.com/21/03/30/nu2.png
Polaris with modded bios: https://i.imgur.com/1Was84K.png
Polaris with original bios: https://i.imgur.com/pkUTTPz.png

I have a xfx 570 8gb (samsung memory), bios flashed, 1150 core clock - 2000 memory clock - 850 mv, most recent driver. Was expecting to get 30mhs, or at least 29, yet only getting around 27.82 https://i.imgur.com/FkrL74g.png.

Does someone know what could be? Such as maybe my bios flash wasn't so optimal, or I'm not tweaking the miner the way I should (i'm not tweaking it all, it's running on auto-tune)
Would appreciate suggestions.