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Buying a Used Graphics Card? What to Watch For

With new GPUs selling for outrageous prices, people are looking everywhere they can to find a graphics card that doesn’t break the bank. For some, a used GPU may be the answer, but you need to take caution when considering this option.

What's the Big Risk?

The greatest risk when buying a used GPU is that you will get one that was used for mining. Cards used for mining are often run at full power for days, weeks, or possibly even months at a time. The constant high level of power running through the card, coupled with the taxing workload and heat, can damage the onboard circuitry and lead to the card failing far sooner than expected. This situation only gets worse if the card wasn’t kept properly ventilated, because miners often try to run as many GPUs as they can in the tightest possible spaces.

Unfortunately, it can be hard to tell if a graphics card was used for mining--in person, let alone if you’re trying to buy one from someone online--and there isn’t any real way to tell how much longer a card will last before failing. If the seller owns up to the fact that a given card was used for mining, it’s best to just walk away.

What to Look For?

Even though miners often seek current-gen, higher-end cards, don’t assume that an older-gen used card hasn’t spent time burning up in a mining rig. Technically, it’s possible to mine cryptocurrency on a variety of desktop GPUs. Although it’s unlikely that low-end cards have been used for mining, you shouldn’t hesitate to question if the likes of an Nvidia GTX 680 or AMD Radeon 7970 is coming out of a mining rig.

COMPARE PRICES OF OLD GEN VS. NEW GEN. If you do opt to purchase a last gen-card in hopes of saving some cash, you should also carefully consider the current price and performance of the GPU. Like newer cards, used cards have also seen an price bump due to the increased demand. For example, if you look at eBay, you can find several used GTX 980s selling for between $300 to $400. The GTX 980 competes with the GTX 1060 in terms of performance. Even if the GTX 1060 is marginally slower than the GTX 980, but they have the advantage of being new, under warranty, with more vRAM, and with lower power consumption, that makes the GTX 1060 an overall better and safer option.

EXAMINE THE BOARD UP CLOSE. Regardless, you should evaluate the risk/reward of buying a used graphics card on a case-by-case basis, because it’s true that there may be some used graphics cards that offer you a better deal than a new one. If you do pick up a used graphics card, you should thoroughly examine and test the card immediately upon arrival to ensure it works properly (presuming you have the option of returning it if it's a dud).

If you see any discoloration on the PCB anywhere on the card, this is a clear sign that the card has been damaged by heat and shouldn’t be trusted to work long.

DON'T STRESS (OR RATHER, DO). You should also run the card through a stress test such as Furmark to see if it’s stable under full load. Some graphics cards in the early stages of failure will continue to work under a light load but fail when pushed to work at 100%. While the test is running, you should also check the fans to make sure they are spinning correctly. Make sure you check the fans during the stress test and not when the GPU is idle, however, as some GPUs turn off the fans when the GPU is idle.

If a used card passes that test, then chances are you got a functional card and likely won’t have to worry about it failing in the near future.

The last thing you want to do is spend time hunting for a deal on a used graphics card just to have it die on you a few weeks later, so take care and shop carefully.

  • Sakkura
    "The constant high level of power running through the card, coupled with the taxing workload and heat, can damage the onboard circuitry and lead to the card failing far sooner than expected."

    That's nonsense. A constant level of power is, if anything, beneficial as it avoids thermal cycling that induces physical stresses on delicate solder joints. And electronics, if properly cooled, can run for many years at full load.

    Inadequate cooling could perhaps be a concern on cards used for mining, as could the wear on the fan bearings.
    Reply
  • 2Be_or_Not2Be
    20743697 said:
    "The constant high level of power running through the card, coupled with the taxing workload and heat, can damage the onboard circuitry and lead to the card failing far sooner than expected."

    That's nonsense. A constant level of power is, if anything, beneficial as it avoids thermal cycling that induces physical stresses on delicate solder joints. And electronics, if properly cooled, can run for many years at full load.

    Inadequate cooling could perhaps be a concern on cards used for mining, as could the wear on the fan bearings.

    But didn't he say a "constant high level of power" - "high" being the key word? So could mean that the card has been overclocked & running non-stop at a high overclock. That, in turn, means at the minimum, the cooling function has been affected as it has to run non-stop in order to keep temps down.

    It also could mean components that weren't designed with higher tolerances could then be stressed more heavily than initially designed/expected. So component failure could also result earlier than desired long-term.
    Reply
  • 2Be_or_Not2Be
    20743617 said:
    With new GPUs selling for outrageous prices, people are looking everywhere they can to find a graphics card that doesn’t break the bank. For some, a used GPU may be the answer, but you need to take caution when considering this option.

    If it seems too good to be true, then it probably isn't. :no:
    Reply
  • redgarl
    It is much more related to the quality of the card than the fact it run at full load 24/7. Basically, it is coming back to the HS design. Most of the time, GPU are undervolt to reduce the powerbill because GPU are usually not well tuned for mining.
    Reply
  • AnimeMania
    If you buy a card that was used for mining, what things do you have to change to get it to run as a gaming graphic card, BIOS, CPU clock, RAM clock, voltage, fan profile? Is there a simple way to reset it back to original specs? Is it possible that malware might have been introduced?
    Reply
  • ccook009
    20743697 said:
    "The constant high level of power running through the card, coupled with the taxing workload and heat, can damage the onboard circuitry and lead to the card failing far sooner than expected."

    That's nonsense. A constant level of power is, if anything, beneficial as it avoids thermal cycling that induces physical stresses on delicate solder joints. And electronics, if properly cooled, can run for many years at full load.

    Inadequate cooling could perhaps be a concern on cards used for mining, as could the wear on the fan bearings.

    You're right about the thermal stress mostly however; there are other aging effects in semiconductors that are negatively effected by constant power. In particular, Electromigration is a huge problem in modern advanced semiconductors. Essentially, uni-directional electron flow causes stress to build-up due to momentum transfer from the electrons to the metal lattice in the chip interconnects. While companies try to design the wires in their chips to be "Electromigration-immortal" they usually have to allow some wires to be susceptible because they don't really expect their customers to have the chips running 24/7 at full load for years at a time. It should be noted that there is a relaxation effect that mitigates electromigration if you let the GPU rest for a while ( But this, as you eluded to, could have consequences as it could result in some mechanical stress). There are other aging effects too, e.g., Time Dependent Dielectric Breakdown, Hot Carrier Injection, and Bias Temperature Instability which can degrade the performance, cause faults in the data, or even permanent failure of the chip.
    Reply
  • Destari
    This is a ridiculous assumption. Miners don't run cards at 100% load and they certainly don't overclock them. Mining is entirely about efficiency, in fact most miners will UNDERCLOCK their cards to reduce thermals and get lower power draw. When mining the primary adversary to profit is power usage, so saying that a miner overvolts or runs a card screaming fast 24/7 is insane.
    Reply
  • jaber2
    As someone who runs a couple 6 GPU rigs I have to say none of this is true, first of all I don't run above 65%, and when you do that you always are running cool between 40 to 60 degrees, the video cards are designed to run hotter and on and off more often, also wanted you all to know I don't plan on selling my gpu's, they will continue running until they die
    Reply
  • raspberrypiguy
    Smart miners will decrease the power limit to 85% and Max out the fan to keep the cards running cool. Although the hashrates are lower the Hash/Watt ratio is more profitable. As long as you don't mess with the voltages or jack up the power limit a modest core and memory overclock is acceptable for mining and the risk of burning out the card is relatively low. Don't put any thing over +400. And don't buy Chinese GPUs that are to good to be true. Also another person commented on thermal cycling. Hot and cold swings are bad for solder points over time. A constent temperature is safer than a swinging one.
    Reply
  • 2Be_or_Not2Be
    20743882 said:
    This is a ridiculous assumption. Miners don't run cards at 100% load and they certainly don't overclock them. Mining is entirely about efficiency, in fact most miners will UNDERCLOCK their cards to reduce thermals and get lower power draw. When mining the primary adversary to profit is power usage, so saying that a miner overvolts or runs a card screaming fast 24/7 is insane.

    I like the points you make about miners & their usage of GPUs. However, caution about used GPUs isn't strictly related to GPUs used by miners; it can be about gamers overclocking like crazy & then trying to trade with someone else.
    Reply