can you tell me how you benchmarked your SCSI system to reach a speed of 32,000 KB/s? I would like to run a comparitive test on a 486 with IDE, to see how far behind it is.

I tend to get 37000 KB/S with a 40 MHz FSB.

Well, I used a SCSI-specific Windows benchmark program from Adaptec (EZ-SCSI). I've noticed that NT4.0 usually puts its IDE hardware as SCSI, so I may be able to test out the CF/IDE benchmark. Its on my list. There are also other benchmark programs. Here are some scores I got in the past on a 33 MHz FSB:

WinTune98, CacheDisk Score = 18.3
WinBen96, DiskMark = 743
Sandra2002, FileSystem = 16006 (20210 for 40 MHz FSB)

I have a PCI-SATA/ATA33 controller (UDMA) known to work well on a 486 so I can test this vs. PIO4 on a 486 and compare it to the SCSI. I have this controller listed in the World's Fastest 486 thread. I'll need to get a parallel installation going, which I don't have time for at the moment. I'm going on holiday for a month shortly.

I don't have any ATA66, ATA100, or ATA133 controllers to test out but am fairly confident that even an UltraWide (40 MB/s) on a 486 will run faster than all of these. I use an Ultra2-LVD (80 MB/s) controller. There was a time when I installed Windows on a PIO3/4 system; it took about 4x as long and, once installed, the system felt slower than slow compared to the same hardware on an Ultra2-LVD SCSI system.

If you are insistent on using a CF card, and want the processing power of SCSI, you might want to consider a CF/IDE-to-SCSI microcontroller converter. ACARD makes them. Unfortunately, I haven't been able to find any reasonably priced ones recently. $130 new, and there's a similar unit on eBay for $135.

If the reason for the CF is quiet operation, not all SCSI disks are loud. Modern ones are as quiet as new SATA drives. I've listed one the World's Fastest 486 Specs that is 137 GB and very quiet. That is another benefit of SCSI, you can use large hard drives without software intervention. Theoretically, an Adaptec 2940U2W (the one I'm using) has a max capability of 2TB. I've been wanting to test some 2 TB SATA drives on it via a SATA-to-SCSI converter.

One last thing about SCSI, if you use a 2940U2W, it has a second connector for SCSI narrow, so you can attach your bootable DVD-ROM drives and boot from disk without having to go into DOS. For me, SCSI vs. non-SCSI on a 486 is a no brainer.

EDIT: For fun I just did a quick Win98SE install on a PIO-4 IDE/CF drive. To say the least, it was a big test in patience compared to installing it with the above mentioned SCSI interface.

Thanks a lot for the excellent info!

feipoa wrote:

...
For me, SCSI vs. non-SCSI on a 486 is a no brainer.

And I see what you mean about the no brainer part. BTW, CF devices come in different speeds. What speed is yours?

133X, 8 GB. 8 GB for guaranteed BIOS compatability.

133X is rated for ~20,000 KB/s.
PIO-4 is rated at ~17,100 KB/s.

Under normal operating conditions, I doubt that any 486 can do 17,100 KB/s under PIO mode, however the SCSI benchmarks shown already do twice that on a 486.

@5u3
Does your Asus PVI-486SP3 BIOS allow for L2 write-through mode at all?

feipoa wrote:

😎 Since it has a SiS chipset, I assume it works with some graphics cards more modern than a Matrox G200. What is the most modern graphics card that you've been able to run in here? Voodoo3, Voodoo2, nVidia Riva TNT2 64?

I have the same board and use a Riva128 with it. However, I'm trying to find a video card with DVI that actually works 🙁

Have you tried the Matrox G450 PCI for DVI support? From way back, I remember that it only works with Intel-chipset boards, so an Asus PVI-486AP4 may work if you have this board. I've never had this motherboard to test myself.

feipoa wrote:

@5u3
Does your Asus PVI-486SP3 BIOS allow for L2 write-through mode at all?

Yes, the L2 cache can be toggled between write-through and write-back in the BIOS setup.

So, uh...what are the differences between Award Bios 4.50g and 4.51g? Differences in tabular columns will be helpful.

The differences so far are only speculative, as was witnessed above. The differences are still an open question. Maybe when I get my retro itch back I'll take a closer look.

The Biostar MB-8433UUD v3.0 may be a good platform to test out these differences as it is flashable with both AWARD BIOS v4.51PG (96/05/20) and v4.50PG (96/03/26).