AGP总线: 为图形加速端口直接跟北桥相连,让图形处理器与系统的主内存直接相连增加传输速率,在显存不足的情况下可以直接调用主内存,分别达到AGP 1X 266MB/S、AGP 2X 533MB/S、AGP 4X 1066MB/S、AGP 8X 2132MB/S,AGP总有132脚,AD线有32条,在维修时可以理解为高速的PCI总线。 A2 4脚为RST B2 4脚为CLK AD 线有32条 VCC=3 .3V, VDD=1.5V
AGP底视图
Pin | A1 | R | A2 | R | B1 | R | B2 | R | 1 | TYFEDT# | | 12v | | 5V | | OVRCNT# | | 2 | USB | | GO-AGP8X | | USB+ | | 5V | | 3 | INTI# | | GND | | INTB# | | GND | | 4 | GNT | | RST# | | REQ | | CLK | | 5 | ST1 | | VCC3.3 | | ST0 | | VCC3.3 | | 6 | RESERVED | | MB-AGP8X | | RBF | | ST2 | | 7 | WBF | | GND | | RESERVED | | GND | | 8 | VCC3.3 | | SBA1# | | VCC3.3 | | SBA0# | | 9 | SB-STBS | | SBA3# | | SB-STBF | | SBA2# | | 10 | SBA5 | | GND | | SBA4# | | GND | | 11 | | | SBA7# | | | | SBA6# | | 12 | | | | | | | | | 13 | AD30 | | | | AD31 | | | | 14 | VCC3.3 | | AD28 | | VCC3.3 | | AD29 | | 15 | AD24 | | AD26 | | AD25 | | AD27 | | 16 | AD-STBS1 | | GND | | AD-STF1 | | GND | | 17 | VDDQ1.5 | | BE3 | | VDDQ1.5 | | AD23 | | 18 | AD20 | | AD22 | | AD19 | | AD21 | | 19 | AD18 | | GND | | AD17 | | GND | | 20 | VDDQ1.5 | | AD16 | | VDDQ1.5 | | C#/BE2 | | 21 | KEY | | FRAME# | | KEY | | IRDY# | | 22 | KEY | | KEY | | KEY | | KEY | | 23 | TRDY# | | KEY | | DEVSEL# | | KEY | | 24 | PME# | | STOP# | | PERR# | | VDDQ1.5 | | 25 | PAR | | GND | | SERR | | GND | | 26 | VDDQ1.5 | | AD15 | | VDDQ1.5 | | C#/BE1 | | 27 | AD11 | | AD13 | | AD12 | | AD14 | | 28 | AD9 | | GND | | AD10 | | GND | | 29 | BDDQ1.5 | | BEO | | VDDQ1.5 | | AD8 | | 30 | AD6 | | AD-STBSO | | AD7 | | AD\STBFO | | 31 | AD4 | | GND | | AD5 | | GND | | 32 | VDD1.5 | | AD2 | | VDDQ1.5 | | AD3 | | 33 | AGPvrefgc | | AD0 | | AGPvrefgc | | AD1 | | AGP的关键信号:和PCI类似,但时钟不同,主要信号来自北桥 复位和PCI并联 |