If increasing resistance does not lower beyond the stock limit, you would need to replace the resistor with a larger one.
I'm not working with any resistor - there's ROG/HotWire port on the card, so to increase voltage I've just shorted the ROG enable points and connected OVM to ground with 3-5KOhm resistor. So OVM allows only to increase voltage - if break it, the voltage will be stock. Maybe it will reduce the VMEM if apply voltage to OVM from, for example, 1.5v battery, but i'm afraid to perform such experiments.
*Have you tried just editing the BIOS to use lower mem clocks before this vmod option? Speed generates heat related failures too..
Tried, of course, 1400 looks pretty stable, but I hope to get 1500-1600 stable with 1.5v. I want to use this card in crossfire and trying to make it symmetric as possible without having to slowdown other card, which is same 280X DC2T and runs 1850MHz without any kind of tweaks.Edited by xfxfx - 2/10/15 at 8:05am