For chips with BGA packaging (usually DDR2 memories) there is a problem: since their terminals are located under the chip, it is impossible to see if the solder was perfect or not. To solve this problem Corsair uses an X-ray machine to check the position of BGA chips terminals.

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Figure 4: Employee checking and correcting solder errors in modules with BGA chips.

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Figure 5: X-ray machine to check the solder of BGA chips.

When a new module type starts to be manufactured Corsair performs temperature tests with this new module in order to ensure that it follows the technical specifications that were set by the engineers. This test is done inside a thermal chamber where an open PC is installed with the memory modules to be tested. This PC runs burn in tests while the temperature inside the chamber varies between 41º F and 113º F (5º C and 45º C) during the test period.

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Figure 6: Thermal chamber.

We also saw how memory modules with stacked chips are manufactured. This technology – only Corsair has this technology, according to them – consists in soldering two chip one at the top of the other in order to obtain a memory module with greater capacity.

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Figure 7: Stacked chips.