The PCI-Special Interest Group earlier stated that the PCIe 3.0 specifications would be released in 2009, with products based on the specification appearing in 2010. The base specification will now be released in the second quarter of 2010, and products could come out one year after that, said Al Yanes, president and chairman of PCI-SIG.
All the groundwork to develop the specification has been done, but the SIG is taking time to verify and guarantee some granular specification details, including backward compatibility and electrical requirements, Yanes said.
"We underestimated the sheer amount of work needed, but it's more work than invention at this point," Yanes said.
PCI Express is a high-speed bus used on a motherboard to link high-speed peripherals or the chipset. The new PCIe 3.0 specification is expected to provide up to double the data transfer rates between chipsets in PCs and use less power compared to its predecessor, the PCIe 2.0 protocol. It will transfer data at speeds of up to 32GB per second.
Many disk controllers or high-speed network controllers tend to be based on PCI Express, said Nathan Brookwood, principal analyst at Insight 64. With the exception of enthusiast PCs like gaming systems, PCIe 3.0 for now may not be needed on mainstream computers.
But networks are getting faster and disks are transferring data at faster rates. The bus has to get faster to support that bandwidth, which is where PCIe 3.0 becomes relevant, Brookwood said.
"We don't need it yet, but we will need it soon," Brookwood said. "Otherwise the bus becomes the bottleneck."
Graphics applications like games will benefit as they are one of the biggest users of computer bandwidth, Yanes said. PCIe 3.0 may also be valuable in servers as they continue to run bandwidth-hungry applications and networking technologies advance, Yanes said.
The products may go into servers and desktops, but graphics products for laptops could also be released, Yanes said.
Some functional enhancements in the specification include smarter data transfers. The TLP processing feature can judge possible data transfers ahead of time, which could allow for faster data transfers. "It's a hint to allow better system performance," Yanes said.
The specification is also backward-compatible, Yanes said. For example, a PCIe 3.0 card can be plugged into a PCIe 2.0 system, or vice versa.
Some of the biggest IT companies have thrown their support behind older and new PCIe specifications. Today the SIG has more than 840 companies on board, including Intel, Advanced Micro Devices, Nvidia, Hewlett-Packard, Dell, IBM and Sun.