PCIe compatibility is the reason for Intel P45 Chipset delay
 

ntel is delaying the launch schedule of its P45 chipset from originally in May to mid-June, according to sources at motherboard makers.

The delay of the chipset is due to problems over compatibility between the chipset's PCI Express x16 port and graphics cards, noted the sources, adding that Intel has notified them that the problem should be solved and ready to launch 2-4 weeks behind the original launch schedule.

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