dwi@manta.NOSC.MIL (Steve Stamper) (05/12/89)
Does anyone know if the GVP 030 board's 32 bit RAM allows DMA Hard Disk controllers like the A2090A and the HardFrame to DMA directly into it? Or must one include a mask in the mountlist like with Ronin and CSA Accelerator boards? I imagine the AT drive interface integrated into there card is much faster in any case. Anyone seen or used this thing? -Roger
daveh@cbmvax.UUCP (Dave Haynie) (05/15/89)
in article <799@manta.NOSC.MIL>, dwi@manta.NOSC.MIL (Steve Stamper) says: > Does anyone know if the GVP 030 board's 32 bit RAM allows DMA Hard Disk > controllers like the A2090A and the HardFrame to DMA directly into it? I hear that it does, but I haven't personally seen a sample yet. The Amiga Sentry has a review or preview of the GVP '030 system this month, if you're looking for more answers. > I imagine the AT drive interface integrated into there card is much faster > in any case. Possibly. The maximum speed of an AT interface is proported to be about 4 megs/sec, same as the maximum synchronous SCSI speed. The maximum speed of the Amiga bus is 3.6 megs/second, so in theory the GVP's 030 could go faster if it ran at 8 megs/second during transfers, no problem for a 25MHz '030 or decent 32 bit memory design. However, most drive mechanics are now the real limiting factor (yes, even those nice Quantums that GVP's been using), so while actual transfer could happen slightly faster, real transfer may be just as disk-limited as with a DMA driven expansion bus SCSI device. About the only way to get an appreciable speed improvement that I've heard of would be to gang together a pair of SCSI's, such that one is seeking while the other is performing a transfer. Not sure that's possible over the AT bus. As for who's really faster, I guess we'll only know when someone does a comparison of this disk speed compared to DMA to 32 bit memory on an '030 system. > -Roger -- Dave Haynie "The 32 Bit Guy" Commodore-Amiga "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: D-DAVE H BIX: hazy Amiga -- It's not just a job, it's an obsession