Here is a press release that gives slightly more information about the survey.
The first-of-its-kind survey explored the political attitudes of video game players, providing a snapshot of their political leanings and positions on key issues. It finds that more than 80 percent of gamers said they anticipate voting in 2016, compared to 75 percent of non-gamers.
In other news, more than 80% of people surveyed on New Year's Eve said that THIS will be the year they finally stop eating junk food and get serious about exercise ;-)
One of the biggest challenges in political polling is that people's statements about their intentions are not very reliable, and people tend to overestimate their intention to vote. The press release states that 80% of gamers and 75% of non-gamers intended to vote in 2016 - but in fact, only about 58% of eligible voters did vote that year, so clearly Ipsos' methods are not reliable for predicting actual turnout.
This can happen even in a scientifically-conducted random sample survey with high response rates, because people are generally bad about honestly predicting their future behaviour. But in this case, the release states that the study was conducted through an online questionnaire.
This adds another major source of error: respondents to these things are generally not representative of the overall population. People who have strong opinions are more likely to participate, which would be likely to exacerbate overestimation of propensity to vote.
There are methods that can be used to mitigate this problem - e.g. you can compare the demographics of your respondents to the general population, and weight under-represented demographics - but they're hard to get right, and it's not clear from the release whether Ipsos even attempted them.
Note that the PDF has distorted the findings that were reported in the press release. It misrepresents "said they anticipate voting" as "will vote", and it removes the comparison stat for non-gamers that might have made it more obvious that this stat was a gross over-estimate. Without that information, a casual reader is left comparing "80% of gamers will vote" with "58% of eligible Americans did vote", which greatly exaggerates the gap.
Also, what is a "gamer"? The scope of the Ipsos survey is: "reported playing video games at least three to four hours per week." That's a very arbitrary cutoff, and also not clearly defined. (Over what time period are we measuring that average?) You could probably get different results by applying a different cutoff, or by being more specific in how that rate is to be measured.