This is a list of MediaTek (MTK) System-on-Chips (SoCs) and phones that use them.
Like many phone chips, you can find the MTK SoC by disassembling the phone. The SoC is usually hidden under an RF shield.
Sometimes this shield will not be removable with just pry tools, and require desoldering. Do NOT try to pry these kinds of shields off, as you WILL destroy the PCB in the process!
On certain firmware dumps, the MTK chipset used may be present after the "MTK_ROMINFO" string.
Engineering mode is a special dial-code that enables various test functions. Do note however that this code varies from phone brand. Most of the time the "engineering mode" code is kind of long, and can be found in unencrypted MTK phone firmware as plain text.
High-speed SIM mode is a feature in the engineering menu in MediaTek feature phones. Once selected, it will count down to 3 and turn off, bricking the phone. It won't turn on again, unless you format it with special flashing software.
Some people report that it also bricked their SIM cards.