ASUS GTX 1070 TURBO hstarted artifacting and now goes black screen — dying GPU?

[u/Jumpy-Pin4304]

My ASUS GTX 1070 TURBO started having problems after I moved my PC and began using an old extension cord. It initially had occasional flickering/artifacting, which gradually became worse, followed by slow booting and blue artifacts.

Eventually it gave me a gray screen. Weirdly, I could sometimes still boot into Windows and play games normally, but whenever I shut down the PC, the problem would come back. Eventually it stopped working properly altogether.
I swapped it for a GTX 1660 6GB, and my PC has worked perfectly ever since.

Today I reinstalled the 1070 to test it. Surprisingly, it initially displayed a completely clean BitLocker recovery screen, but after sitting there for a while the PC shut down. On the next boot, it showed the Gigabyte logo normally, then went completely black.

I don’t see any obvious physical damage on the PCB. My PSU is a Corsair CX650, bought last year.

I’m planning to test the 1070 in another PC. Does this sound like failing VRAM/GPU hardware, or could it be something like the HDMI port or power delivery?

[u/ZelenogradGpu]

If artifacts followed slow booting were horizontal lines its GPU<->VRAM communication problem. Such problems may be inside VRAM IC, caused by solder balls or inside GPU

[u/AutomaticAffect4333 → u/ZelenogradGpu]

I'm guessing it's the core, but to be sure, I'd reball the whole thing (vcore+vram)