Could someone share their hard disk benchmark results for a VLB SCSI card, e.g. Adaptec AHA-2842A (with & without smartdrv), compared with a caching IDE VLB card, e.g. Tekram DC680-T, using an Am5x86 or Intel DX4 in write-back mode? Thanks!
I would think either solution is bottlenecked by the VLB interface with newer fast drives (IDE or SCSI).
Collector of old computers, hardware, and software
The SCSI card has to be a DMA model, or it's not really a fair comparison. (AHA 2842x IS bus mastering DMA)
"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium
Do you know which VLB SCSI cards properly support DMA? This comment indirectly mentions DMA and the 2842A,
http://www.adaptec.com/en-us/support/_eol/scs … ng_aha-2840.htm
Back in the day Adaptec VLB cards were NOT as popular as their ISA and later PCI models. Adaptec cards simply had a few more (minor) issues than the competition.
Buslogic was a favourite, for example. This guy settled for one with proper DMA and bus mastering (jump to roughly 25% of the page, component No. 9) :
https://ancientelectronics.wordpress.com/2012/07/
As mentioned earlier, some late SiS 471 motherboards claim to have the issue (SCSI busmastering controllers versus L1 write back cache) fixed. Needs to be checked.
"Ita in vita ut in lusu alae pessima iactura arte corrigenda est."
Interesting. I have not had any problem (yet?) using my Adaptec AHA-2842A with the SiS 471 chipset in write-back mode. Win95c installed fine anyway. I wonder how that BusLogic BT-445S compares against the AHA-2842A?
