The U2415 comes with a user control for the overdrive impulse available within the OSD menu in the 'display' section as shown above. This is rare for a Dell screen as normally you end up being reliant on the factory setup and often this has lead to issues with overshoot on some models (e.g. Dell U2413, U2713H, U3014). There are two options available here in the menu, for 'normal' and 'fast' modes.
First of all we carried out a smaller sample set of measurements in both of the 'Response Time' settings. These, along with various motion tests allowed us to quickly identify which was the optimum overdrive setting for this screen.
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The overall gaming performance of the Dell U2415 was very good and we were pleased with what Dell have done with the response time control. This is the first time they've made a response time setting available from the normal OSD and it's nice that they've not forced an overly aggressive overdrive impulse on us like they did on some previous models (e.g. U2413, U2713H). Instead, the two response time settings allow you to choose the best option for your needs. The 'normal' mode was our preferred option, giving a fast (for IPS) response time of 8.6ms G2G, without introducing any real overshoot. A success really for this type of panel technology. It is a screen lacking higher refresh rate support or any advanced gaming features like blur reduction modes or G-sync, but as a general screen with decent IPS gaming performance, it's impressive.