PCIe显卡，16对 Receive 信号是闲置的吗？

Quantum_

1. x16 的显卡， 共有HSI(0)n/p ~ HSI(15)n/p 16对Receive信号（显卡到CPU）.
2. 显卡只是一个输出设备，只接收CPU的输出， 并不需要与CPU高速交互。
3. 那么， 第1点描述的16对线， 是否就一直是闲置的？ (这么浪费，有点不可思议！特发此问）
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**参考文书：
https://en.wikipedia.org/wiki/PCI_Express
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超級狗

PCI Express Basics and Background
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Quantum_

Dear Super
2 S2 s! L: e8 X! H# o1 \I still can't understand what happened to PCIe receiver signals to make them transmit signal from Device to Host, after reading your attachment carefully.
% d6 E- |; c, g9 Y* w1 ?Do you mean that the answer of my question is concluded in the chapter below?
. P/ w- Q" H! ]( p5 `$ q4 X0 L"Credit-based flow control is point-to-point based, not end-to-end, "
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"Split Transactions"
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+ B3 _+ |/ X. R' h: S; CDo you have any other stuff for a rookie EE to learn about the PCIe Dispaly Card.

Thanks very much.
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ykwym

PCIe的有些包发出来是需要接收端发信息回去，确保包是一定被收到的。so。。。

alexfu1984

就需要这个东东，好就一个字