1. Different Maximum Data Rates:
PCI-E 2 can only provide a maximum data rate of 5GT/s, while PCI-E 3 has a data transfer rate of 8GT/s, which increases the bus bandwidth.The PCI-E 3.0 specification increases the data transfer rate to 8GHz | 8GB/S (initially also expected to be 10GHz), maintains PCI -E 2 backward compatibility. x/1. and continues to support 2.5GHz and 5GHz signaling mechanisms.
2. different encoding methods:
PCI Express 3.0 operates at 8GHz and eliminates the legacy 8B/10B encoding. It will introduce a number of technologies, including enhanced signaling, data integrity, transmission and reception equalization, PLL improvements, time pulse data recovery, and general extensions.
Extended Information:
1. Pci-e2.0 is highly efficient due to its increased transmission frequency. For example, an x16 graphics slot can deliver up to 16GB/s transfer performance, which is great for data-intensive devices such as advanced graphics cards, coprocessor acceleration cards, and more.
2. PCI Express 2.0 also brings some new technical features, such as PCI Express 2.0's new Dynamic Link feature. The system can dynamically and continuously adjust the bus speed as needed to reduce power consumption. This feature is especially useful for mobile devices that require maximum power savings.
3. The PCI Express 2.0 specification features access control. In point-to-point data transfers, software can control the routing of packets over the interconnecting network, preventing hackers from stealing data through spoofing or data re-routing.
References:
Baidu Wikipedia - pci - the world's first online dictionary. p>Baidu Encyclopedia-pci-e 3.0
Baidu Encyclopedia-PCI Express 2.0