Digging into a RX 470 targeted at cryptominers.
There has been a lot of news lately about the release of Cryptocurrency-specific graphics cards from both NVIDIA and AMD add-in board partners. While we covered the currently cryptomining phenomenon in an earlier article, today we are taking a look at one of these cards geared towards miners.
It's worth noting that I purchased this card myself from Newegg, and neither AMD or Sapphire are involved in this article. I saw this card pop up on Newegg a few days ago, and my curiosity got the best of me.
There has been a lot of speculation, and little official information from vendors about what these mining cards will actually entail.
From the outward appearance, it is virtually impossible to distinguish this "new" RX 470 from the previous Sapphire Nitro+ RX 470, besides the lack of additional display outputs beyond the DVI connection. Even the branding and labels on the card identify it as a Nitro+ RX 470.
In order to test the hashing rates of this GPU, we are using Claymore's Dual Miner Version 9.6 (mining Ethereum only) against a reference design RX 470, also from Sapphire.
On the reference RX 470 out of the box, we hit rates of about 21.8 MH/s while mining Ethereum.
Once we moved to the Sapphire mining card, we move up to at least 24 MH/s from the start.
There's a lot of tuning of these cards that can be done to increase the mining rates and profitability ranging from undervolting to reduce power consumption, all the way to custom VBIOS options to increase the hash rate for a given algorithm.
This is part of the reason why Sapphire is selling these GPUs in two different SKUs, calling out the use of Samsung memory versus other vendors. Memory vendor can make a huge difference when overclocking these cards for mining purposes, and when developing custom VBIOS. It's worth nothing that our reference RX 470 has Hynix memory, while the mining SKU we ordered has Samsung memory.
Given all of the variability in tuning these cards to increase the mining rate, I won't be getting much more into a performance comparison. From everything we've seen, it behaves as expected for an RX 470 GPU in terms of overclocking and VBIOS.
It's worth noting that the "new" RX 470 seemed to be more power efficient while achieving a higher hash rate. Average power consumption in the stock configurations showed the mining card using 8W less. Not exactly mind blowing power consumption reduction, but when the card is running 24/7, it can make a difference.
Both cards could be undervolted by 20% without losing significant hash rate (less than 1 MH/s). When undervolted, these cards performed at roughly the same power levels.
Instead, I wanted to take a look at what other limitations might be found on this card as opposed to normal graphics cards. There has been a lot of speculation about things like display outputs (which we obviously can see this card has), and things like crossfire support with another RX 470.
Using this mining card as the only GPU in an X299 system, it functioned exactly as expected. We ran into no additional limitations placed on this card. Additionally, with our reference RX 470 installed, we were able to enable Crossfire with no problems (in fact, the driver did it automatically when we booted with both cards installed.) A quick run of 3DMark verified that Crossfire was indeed working as expected.
So that leaves us in an interesting position. When rumors of these "mining specific graphics cards" were first being discussed, people were talking about potential tweaks to make them appeal to miners, but not general gamers. It appears this really isn't the case. The only detriments with this Sapphire RX 470 are the fact that it only has one physical display connection (likely to cut costs in manufacturing for Sapphire), and the very limited 180-day warranty.
However, if you are looking for an RX 470 and you manage to come across one of these cards if you are only looking to use DVI (or HDMI with an adapter), then this card will function fine to you.
In fact, I would imagine these cards will be available in the near future as Ethereum mining gets more difficult and people become less interested in cryptomining again.