Dell only allows Dell branded cards on some of their models. You ought to get a dell wireless 1550 card rather than 7260
Intel does not support Integration and that is when the original wireless card is replaced for another one. Please keep in mind that wireless hardware installation and use is subject to regulatory approval and the new adapter may not support local regulations. Only your system manufacturer is entitled to provide the list of validated and certified adapters that are compatible with your system, so for more information we recommend that you contact them directly. Furthermore, Intel(R) Wireless Adapters are meant to be professionally installed the OEM (Original Equipment Manufacturer) technicians on certified systems only as they customize the adapter and features may be added or removed, voltage alterations...etc. Please check the links below for more information on this subject.
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