What are the benefits of In-Socket Accelerators (ISA) over PCI, PCI-X, or PCI-Express Cards?
Since ISAs sit in a CPU socket they have a lower latency, higher performance interconnect to the CPU and/or chipset. This allows the ISA to be a peer to the CPU, handle interrupts, and be a master in the system, something that being a PCI/X/E slot does not allow. HyperTransport offers multiple links at 16 bits at 800MT/s and Front Side Bus is 64 bits at 1066MT/s, which is greater bandwidth than PCI-Express at x4 or x8 and lower latency as well.
