Q: How to replace plcc(square-32pin) bios?
Ans: Make sure the board is not powered on, while removing & replacing the chip. The safest way is to remove the power cord. When placing a new chip, align the flat (notch) corner of the chip to the socket. There is only one flat corner so its should fit in one and only one correct way.
Q: Where is this bios chip number located?
Ans: For plcc32 bios (square), chip number is marked on top.But usually motherboard makers put sticker label on top. So, remove the sticker label to reveal the bios chip number, it should read like SST49LF040B or W39V020AP or PM49FL004T (sample chips number only, yours can be different).
Q: How to replace SPI flash in socket (4x4pin DIP) and DIP flash(16x16pin)?
Ans: Before removing the old bios,take note where is the chip notch aligned.This notch is a circle mark at the edge of the chip. Then put the NEW bios, just follow the same alignment as the old bios. This is easy but critical!!Since if you reversed the placement, you either end up a dead board or a dead bios. So be carefull.
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