Radeon X1550

Is this a work in Radeon X1550 AGP 4x slot?
Also, nobody knows what version of Pixel and Vertex Shader support?

The Radeon X1550 AGP 8X support, but it should work, but @ 4X.
It has 4 texture units, 4 ROPs, 4 pixel shaders and vertex shaders 2 Support for Microsoft ® ® DirectX ® 9.0 Shader Model 3.0 programmable vertex and pixel shaders.

Hello mate
The Radeon X1550 is an AGP x8 However, if you are using a 4x AGP slot then it will work fine, but just to return to the AGP 4x speed
X1550 uses the pixel shader model 3.0 and comliance and open GL 2.0
Other specifications include a memory bandwidth 12.8gb/sec, core clock 550 MHz and 512 MB of DDR2 memory running at 400 MHz (800MHz DDR effective)
2200 shader operations per second, 2200m/pixels / sec fill pixel, 275 MVertices / sec Vertex Operations
its manufactured using 80nm (nanometer) process, and four pixel pipelines
second, it is essentially a mid-range card and play games more modern and smaller resolutions (1024x768 / 1280x1024)
the 550MHz base clock is good for any card, and combined with the bandwidth 12.8gb/sec is equal to a card like the GeForce 7600GT
no problem let me know
good luck mate!