icewaere, put Your DMM to lowest resistance reading (ie 200ohm). Put one stick to some GND You know (ie GND in PCIe connector) and with other end start measuring the SMD components. It must read 0,00ohm, so You'll know its GND.
When You have find the right one, put Your DMM to bigger resistance(ie 20kohm) and measure the resistance between two sides of that component. Then use a pencil to lower resistance. Don't forget to check the resistance drop after every stripe You have done.
Lower the resistance for example 10% at first and then turn on Your PC to check, how much Vgpu rised!