Over the weekend, I'll be supplying facts to be added to the spec sheets. Some of the details I provide are for the "FPGA prototype" sheet, some are for the "OGD1 graphics card" sheet, and some are for both.
The projected power requirements are "between 18 and 23 watts". Below are some performance comparisons to be put into a table. All pixels are 32 bits. Where exact numbers are not available or published benchmarks are ambiguous, estimates are made by calculating from available numbers. The unit 1Mp is equal to 1,000,000 pixels. All numbers are given in units of Mp/s, unless otherwise stated. For each performance figure, I assume that the display resolution is [EMAIL PROTECTED] That means the display is going to require 78.6Mp/s. Assuming about 5% overhead, we'll use a round figure of 83Mp/s in comparisons. Performance numbers attempt to take this into account. I'm comparing three cards: (1) OGA running on OGD1 (2) GeForce 2 GTS [http://techreport.com/reviews/2000q2/geforce2/] (3) Radeon 7000 PCI [http://www.newegg.com/Product/Product.asp?Item=N82E16814102447] [http://www.scan.co.uk/Products/ProductInfo.asp?WebProductID=47607] Performance measure OGD1/OGA GeForce 2 GTS Radeon 7000 PCI Memory clock rate (DDR MHz) 350-400 333 300 Memory bus width (bits) 128 128 64 Video memory (MiB) 256 128 64 Pixel pipelines 2/4 4 1 Maximum display resolution 6144x2048 ?? 2048x1536 Total memory bandwidth 1600 1333 600 Memory bandwidth minus video 1517 1250 517 ? Usable memory bandwidth 1350 1060 ? 430 GPU clock rate (Mhz) 150-200 200 150 Maximum GPU pixel rate (2D) 600-800 800 ? ?? Maximum GPU pixel rate (3D) 300-400 800 150 Solid fill (2D) 600-800 800 ? 430 ! Gouraud shaded fill (3D) 300-400 800 150 ? Bitblt (2D) 600-675 530 ? 190 ! Single-texture fill (3D) 300-400 530 ? 150 ? Bitblt+XOR (2D) 450 353 ? 129 ! Two-texture fill (3D) 300-400 353 ? 143 ? Polylines (2D/3D) 150-200 200 ? 44.5 ! Notes: ? Indicates a figure that is based on estimation and extrapolation. ! Indicates a figure that comes from real benchmarks. The OGA video controller's physical resolution limit is at least tens of thousands of pixels horizontally by tens of thousands vertically. However, each video output has a maximum pixel rate of 330 Mp/s. The value of 6144x2048 was therefore chosen as a practical maximum for a frame rate of between 50 and 60Hz. OGD1/OGA performance figures are calculated based on projected clock rates, and design characteristics. GeForce 2 GTS performance figures are estimates based on published benchmarks from reviews. Radeon 7000 PCI performance figures are based on actual x11perf tests, using the open source Radeon drivers. However 3D performance figures are estimated from 2D performance figures and published clock rates and design characteristics. _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
