Classic computing fanatic Peter Seibold has discovered a brand new use for the Accelerated Graphics Port (AGP) discovered on PC motherboards of a sure classic — due to an adapter that converts it to a high-performance 66MHz Peripheral Element Interconnect (PCI) port as an alternative.
“The most important bottleneck of the Tremendous Socket 7 platform is the shared bandwidth of the PCI bus,” Seibold explains of the explanation for his uncommon adapter, “with a theoretical most of 133MB/s however extra like 60-90MB/s on this platform. There is no means I can get even near gigabit line pace with my Socket 7 NAS [Network Attached Storage appliance] with the gigabit NIC and the SATA controller related to the identical bus.”
For many, that may imply it is time to select new {hardware} — however for Seibold, whose motto is “constructing useful resource environment friendly techniques from out of date elements,” there was another: the AGP slot. Launched in 1997, the Accelerated Graphics Port (AGP) normal took the Peripheral Element Interconnect (PCI) bus and tweaked it for high-performance — by the requirements of the period — graphics playing cards.
Whereas a NAS would not actually need a high-performance graphics card, the AGP slot does present what’s successfully a second and fully impartial PCI bus — and one which may switch knowledge significantly sooner. “With my prototype of an AGP to PCI adapter,” Seibold explains, “we are able to truly use it for one thing else [other] than the graphics card.”
After proving the idea with a breakout board and a few hand-soldered wires, Seibold designed a neater adapter board. (📷: Peter Seibold)
Utilizing the AGP slot as an alternative of the contentious PCI bus, Seibold is ready to maintain a switch fee from the NAS of greater than 200MB/s — over twice the speed achievable utilizing PCI gadgets alone. The one catch: normal 33MHz PCI playing cards aren’t appropriate with the AGP slot. 66MHz PCI, and PCI-X playing cards, although, work effective, Seibold discovered.
Seibold is promoting compact adapter boards, primarily based on the spaghetti-wired prototype, on his web site for €9.90 PCB-only, €29 with a PCI connector, or €39 as a fully-assembled unit ready-to-go.