I am pretty happy on the stability now. Just need to get the bar in place to hold those expansion cards in place. Also looking to add two more GPUs. I was now able to flash all the bios of all the gpu however, I am unsure how everyone is setting the VDD versus MVDD. Can someone help with this? I think I am setting the wrong field. Memory voltage versus Memory core voltage?
On top of this question, is that I read that it’s really about Mem and not Core; however, I see my hash rate increase when I increase the core where Mem seems to not impact anything. According to hive.
there are three kinds of voltages in Polaris (RX 470/570/480/580/590)
Core voltage - AKA “VDD” - The GPU core voltage
Memory voltage - AKA “MVDD” - The voltage at which the RAM chips themselves operate.
Memory controller IO voltage - AKA “VDDCI” - The voltage that the IO bus between the GPU and memory operates.
On Polaris, you can’t change the MVDD so the only things of interest is VDD and VDDCI.
By lowering them you can reduce the amount of power consumed by the card.
I have found another issue with my rig. Today, I have realized that my 900w power supply that powers my GPUs has a short at the power outlet. It started today and I can visibly see where the connection is loose. I’m contemplating moving my GPU to the 850w power supply that is powering the mobo, risers, and fans. However, I am not 100% sure how much power those devices are using.
Is there a way to know the consumption of that 850w with the mobo, riser, and fans?
Below is the total consumption as reported by HiveOs.
There’s really no way to judge how much power the rig is using without a clamp multimeter or a “kill-a-watt” meter.
Your 850 watt ATX PSU may not even be a true 850 watts, but possibly a lot lower. The 850W rating of most ATX PSUs is a combined rating that includes 12V, 5V and 3.3V rails together.
You’d need to find out the 12V wattage rating of your PSU and make that decision.
Since the GPUs use only 12V power it might not a good idea to use it to power the whole rig.
Of course, it depends on the PSU… some PSUs are badass monsters that have incredible output capability… and others are nothing but trash inside a metal box.
I use a wall Watt Meter to monitor Rig wattage. Hive watts are less than wall watts since it only sees GPU’s. For example Hive shows 386 W for four(4) RX580’s but I read 480 at the wall. I’m able to account for the discrepancy due to PSU efficiency, Fans, and MOBO draw. BTW - everything is powered from 1200W HP server supply.
