Hi expert,
Customer met reduction of speed on PCIE, there are 3 TCI6608 on one board. We observed on one of DSPs PCIE speed was downgrade from 5Gbps to 2.5Gbps.
1. We did test on 5 boards, only one board had issue.
2. Then we measured PCIE serdes TXP/N resistor value to ground on these five boards. Failed board is 7.5K and the other four boards is 40K.
3. We measured power supply on failed DSP and no short circuit.
Questions are
1. On the failed board, TXP/N resistor of three DSPs are 7.5K but only one DSP downgrade PCIE speed. Is this resistor value a problem?
2. We don't see any problem on power supply, could you please suggest other debug option to address the root cause?
Thank you.
Allen