Without having used one, I'd think that part of the speed advantage disappears because the SCSI bus speed and the speed of the interface between SCSI and motherboard serve as bottlenecks. Furthermore, I would expect that there needs to be cache present on the drives themselves to minimize further performance issues. Finally, several older SCSI controllers have an 8 Gb limit for hard disks.

There will be some advantage: most of the gain from an SSD comes not from the sequential transfer speeds but from the reduction in seek latency, the fact that what latency remains is mostly constant, and the resulting massively increased random read/write performance and attendant increased IOPS. Attached to Ultra320 SCSI, they'd probably feel almost exactly like modern SATA/SAS versions, even if you could benchmark out a difference.

On a slower SCSI bus, or a SCSI controller bottlenecked by a PCI32/33 or even ISA connection, obviously they'd be slower, but the super-fast seeks and the fact that all IO, even random small writes, will probably saturate the bottleneck, will mean they're still faster than spinning rust would be.

I found this article:¨
Creating a SSD for my Macintosh SE/30
https://duxbridge.wordpress.com/2012/01/15/cr … macintosh-se30/

but 50pin IDE-SCSI converter is only 20MB/s SCSI-3 interface:
http://web.archive.org/web/20060312063515/htt … DSC-E050418.pdf

And industrial SCSI SSD sollution. Again with CF card:
http://www.cf2scsi.com/index.php/products/fix … #specifications
But again with 50pin narrow, not 68pin interface. And only FastSCSI-2 with 10MB/s.

Yes... They are more or less what most people are thinking about, them CF cards and IDE/SCSI converters.
However. I was thinking in terms of these kind of drives. I regard them as more sort of "real" drives.

http://www.memkor.com/products/white-series/

20mb/s is however not much, though in a 286/386 system, I think they are extremely fast solutions.

I'd like to get my hands on one to test it - they'd be great in old Suns and SGIs, too. And again, the latency improvement on an SSD means they'll feel fast as greased lightning, even though the transfer rate is thoroughly mediocre (though for the day, it was fantastic - and with an SSD you'll probably see it maxed out for everything, not just for the ideal case.)

brostenen wrote:

Yes... They are more or less what most people are thinking about, them CF cards and IDE/SCSI converters. However. I was thinking […]
Show full quote

Yes... They are more or less what most people are thinking about, them CF cards and IDE/SCSI converters.
However. I was thinking in terms of these kind of drives. I regard them as more sort of "real" drives.

http://www.memkor.com/products/white-series/

20mb/s is however not much, though in a 286/386 system, I think they are extremely fast solutions.

Not sure how would you get 20MB/s on a ISA bus system?

You wouldn't, but you would get the max that the ISA bus could sustain: IOW, the bus becomes the limit pretty much 100% of the time, rather than the disk being the limit.

kixs wrote:

brostenen wrote:

Yes... They are more or less what most people are thinking about, them CF cards and IDE/SCSI converters. However. I was thinking […]
Show full quote

Yes... They are more or less what most people are thinking about, them CF cards and IDE/SCSI converters.
However. I was thinking in terms of these kind of drives. I regard them as more sort of "real" drives.

http://www.memkor.com/products/white-series/

20mb/s is however not much, though in a 286/386 system, I think they are extremely fast solutions.

Not sure how would you get 20MB/s on a ISA bus system?

Ahhh. Yes. My bad. It will be less.
Anyway, it will probably be maxed out. 🤣

jade_angel wrote:

I'd like to get my hands on one to test it - they'd be great in old Suns and SGIs, too. And again, the latency improvement on an SSD means they'll feel fast as greased lightning, even though the transfer rate is thoroughly mediocre (though for the day, it was fantastic - and with an SSD you'll probably see it maxed out for everything, not just for the ideal case.)

Same here, if the drive will be a stable one of the kind.
So I wanted to ask before looking for prices and trying to hunt one down. They might be expensive, yet they will look a bit better and "right" in a 286/386/486.

Noise and heat issue might be a thing of the past.

Wow, Sandisk produced Ultra320 SCSI SSD drives 10 years ago. With 336GB and 352GB in 2006-7.
https://media.digikey.com/pdf/Data%20Sh ... %20320.pdf

3.5 inch drive backward compatible with U160 and 40, 20 and 10 MB/s modes. (not 80MB/s).
U320 SCSI is faster compared to SATA2/300 but because age it was only burst speed to cache.
Read and write speed is listed only 40MB/s.

I don`t know how much drive cost but IMHo it was price of a sport car.

I found some converters with fastest paralel SCSI Interfaces from ACARD and Addonics:
U320:
http://www.2san.com/english/products03.jsp?id … d=null&pg_id=71

U160:
http://www.addonics.com/products/adsalvd160.php

and "cheap" slow SCSI-CF AztecMonster adapter for old devices:
https://www.alibaba.com/product-detail/CF-Azt … 0006276834.html
here used with Amiga:
http://amigax1000.blogspot.cz/2014/08/cdtv-in … roller-and.html

LVD 80 MB/s:
http://www.addonics.com/products/adaec7722.php

Some time has passed since this started, but it has such good links that it would be a shame to start a new thread and repeat all that history.

I'm wondering if anyone has yet to try one of these CF-to-SCSI solutions? In particular, https://cf2scsi.com/index.php/products/scsi-d … te-drive-detail . It also comes in a 68-pin flavour, https://cf2scsi.com/index.php/products/scsi-d … or-to-cf-detail

The product brief is here, https://cf2scsi.com/datasheets/SCSI_Bridge_Em … lator_to_CF.pdf and https://cf2scsi.com/Press-Releases/SCSI-Flash … t-Final_all.pdf

I was kind of wondering if these devices really exist or if this was more of a preliminary to gauge market interest?

The Sandisk Ultra320 SCSI SSD that was noted does exist and you get get them for $500 for 64 GB. https://www.ebay.com/itm/392273859970

feipoa wrote:

I was kind of wondering if these devices really exist or if this was more of a preliminary to gauge market interest?

The Sandisk Ultra320 SCSI SSD that was noted does exist and you get get them for $500 for 64 GB. https://www.ebay.com/itm/392273859970

I remember seeing that site when I was looking for an SCSI converter but couldn't find pricing or a where to buy page. I didn't bother contacting them. But maybe someone can, be sure to ask for some test samples.

IMO, the Acard SCSI adapters are the best available. I have an Acard SCSI to SATA disk/SSD and an Acard SCSI to IDE CD/DVD. The disk adapter works with single ended wide/ultrawide all the way to LVD-160. Unfortunately for me, the SCSI2SD is dog-slow. I'd only use it with a 386 or lower computer.

Those adapters that Addonics sells are actually Acard adapters. It might be less expensive to buy them from Addonics.

You could get two new Acard adapters and two SATA SSD for less than that used Sandisk. Another eBay seller overvaluing a product.

FuzzyLogic wrote:

Unfortunately for me, the SCSI2SD is dog-slow. I'd only use it with a 386 or lower computer.

Really? I compared the ACARD+CF and SCSI2SD in my 486SXL40 and found them to be about the same speed. I put the same CF card into a 430HX system (w/P233) using onboard PCI IDE (vs. the ISA SCSI in the SXL) and the speed was about the same as in the SXL+SCSI+ACARD+CF. SCSI2SD - Comparison of SCSI SD, CF, and HDD performance

feipoa wrote:

Really? I compared the ACARD+CF and SCSI2SD in my 486SXL40 and found them to be about the same speed. I put the same CF card into a 430HX system (w/P233) using onboard PCI IDE (vs. the ISA SCSI in the SXL) and the speed was about the same as in the SXL+SCSI+ACARD+CF. SCSI2SD - Comparison of SCSI SD, CF, and HDD performance

I haven't looked at your benchmarks yet (it's a lengthy read.) But I have the Wide LVD-160 to SATA version coupled with an SSD and it's fast. I just ran Speedsys on my lowly 430NX Pentium and pulled around 30MB/s linear read speed. I need to try it on a faster system to see if it makes any difference. The SCSI2SD was (if I can remember correctly) barely in the 2MB/s range on the same LSI HBA and also on a Buslogic HBA.

I can't speak for the quality of the SCSI models, but I have a IDE flash module installed in my 386 machine at the moment. It is a 4 GB flash dongle, and it plugs directly onto the header of the IDE drive. It works flawlessly, and I've never had any trouble with it at all. Most of them are designed to emulate a certain drive type, so that they have at least semi-normal drive parameters. Some of the cheaper alternatives have strange geometry specs that confuse the controller.

I haven't looked at your benchmarks yet (it's a lengthy read.) But I have the Wide LVD-160 to SATA version coupled with an SSD and it's fast. I just ran Speedsys on my lowly 430NX Pentium and pulled around 30MB/s linear read speed. I need to try it on a faster system to see if it makes any difference. The SCSI2SD was (if I can remember correctly) barely in the 2MB/s range on the same LSI HBA and also on a Buslogic HBA.

only 30mb/s ?

i get around 70mb/s with Pentium 166 and a 3ware 9500 Sata / 40Gb Intel SSD

matze79 wrote:

only 30mb/s ?

i get around 70mb/s with Pentium 166 and a 3ware 9500 Sata / 40Gb Intel SSD

Yes. It's a 430NX system PCI performance isn't great. Plus there's a converter in between translating SCSI to SATA.

I think I got faster reads when I used a PCI to SATA card. But there were no Windows 3.1x or 95 drivers for the three cards I tested.. With this LSI card I can boot from CD/DVD and get 32bit file & disk access in Windows 3.1x and Windows 95.

Back to the SCSI2SD. I found out that there is a newer version that has much better performance. But it's still maxes out at 10MB/s Fast SCSI speeds. Time to make an Ultra Wide version. Or one that uses M.2 SSDs. SD cards tend to wear out when running an OS on them.