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Received: by minnie.vk1xwt.ampr.org with NNTP id AA916 ; Tue, 09 Feb 93 19:00:05 EST Path: sserve!manuel.anu.edu.au!munnari.oz.au!sgiblab!spool.mu.edu!uwm.edu!ogicse!flop.ENGR.ORST.EDU!gaia.ucs.orst.edu!umn.edu!csus.edu!netcom.com!hasty From: hasty@netcom.com (Amancio Hasty Jr) Newsgroups: comp.unix.bsd Subject: Re: ATI Mach32 and Xfree86 or XS3? Message-ID: <1993Feb6.051805.276@netcom.com> Date: 6 Feb 93 05:18:05 GMT Article-I.D.: netcom.1993Feb6.051805.276 References: <1993Jan29.193936.13423@netcom.com> <1993Jan29.225541.20260@Informatik.TU-Muenchen.DE> <TMH.93Feb6014407@keks.first.gmd.de> Organization: Netcom Online Communications Services (408-241-9760 login: guest) Lines: 39 The 801 and 928 are capable of mapping their entire video ram address space into the host memory. The 805 has as 26bit address field to map the videoram. For a chipset that is not quite a good fit for the X architecture it has generated faster graphics that any PC X server which I heard of and with the 928 it will be faster than the sun workstation ipx/gx by more than 30%. BTW: the 801 at 1024x728 60MHz is faster than the ATI Ultra Pro. On the Dos arena please read Jan 93' Byte, S3 vs. ATI Ultra pro, the 801 won. XS3 does use vga banking and we are looking into mapping the entire videoram memory. Perhaps, at an address range higher than 32MB. As for it being a 16bit interface on the local bus we can address the 805 and the 928 using a 32 bit interface. I am not sure that this will help performance. On local bus, the bottleneck on the fixed graphic accelarateror chips is more on the VRAM or DRAM refresh cycle. The latter according to Thomas Roell suffers more as the dot clock increases. Also, this has been empirically confirmed by Jon Tombs and I. What will be nice to have today is 3D hardware support also the ability for the chip to perform bitblt operations via DMA. Currently, we read and write images to the vga in a tight loop which performs banking as neccessary. While we argue about ATI vs S3 vs who knows what, the amiga/videotoaster folks are making commercials and animation for TV series like Babylon 5. Hope this helps, Amancio Hasty -- This message brought to you by the letters X and S and the number 3 Amancio Hasty | Home: (415) 495-3046 | ftp-site depository of all my work: e-mail hasty@netcom.com | sunvis.rtpnc.epa.gov:/pub/386bsd/incoming