Truly hope things get fixed soon so you don't have to leave it behind, you've done an excellent job keeping it afloat with very little to work with from the sound of it.
It looks like millrkllr88 has SLI working on the Aqua Z490 with a pair of GTX 480's.
https://hwbot.org/submission/4485341_mllrkllr88_3dmark11___performance_2x_geforce_gtx_480_15064_marks
So would disabling cores on a quad be cool for these?
3dmark06:
DDR3: 3 processor cores and 3 GPU cores
Unigine Basic:
DDR3: 2 CPU cores, Geforce 400 family