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On your Ethernet speed test ... how was that measured? (Is that a raw TCP/IP sockets performance number reported by the mTCP speed test program or is that an FTP number? If it is FTP is that reading or writing?)

No, I have not yet tried the mctp speed test. Will do so. I see it is necessary if to be compared with other results objectively.
Yet I have measured what is most important to me, a best scenario usage: FTP big file copy, from a Win 7 machine, Total Commander ftp session to the 486. The reverse direction is somehow* under 330 kb/s, but I rarely upload anything from retro machines to the modern ones.

* I suspect the beta 0.8 packet driver that works for this card has room for improvement, but at least there is a working packet driver for it 😀

Running MTCP spdtest...
Here's what I got between
this VLB system overclocked to 160 (4x40) Mhz
and
an IBM PS/1 2133 (CPU DX/2 Overdrive 66 running at 50 Mhz):

4194304 bytes both sent and received in 5.566 sec, effectively 753588 byte/sec, about 735.89 kb/s 😀

I think your card is actually faster than those numbers indicate; the bottleneck is probably the PS/1 on the other side.

Just for comparison purposes I have these measurements:

Clone 80386-40, ISA bus Davicom card, 32MB transfer: 690KB/sec sending, 957KB/sec receiving
Compaq Deskpro 433i with a 3Com 3C509B, 32MB transfer: 913KB/sec sending, 1010KB/sec receiving

The theoretical limit for TCP/IP running on a 10Mb/sec Ethernet is around 1130KB/sec by my calculations, ignoring the time needed to process the occasional ACK packet. Your machine should be doing at least as well as the Deskpro - try measuring against a faster machine and you should be able to saturate the wire.

OK, next time I will check it against at least a Pentium with a 100 mb/s PCI NIC...

When I tested my dual pentium pro's network system, the other computer was a new xeon system. The point of testing is to only test ONE thing at a time and to limit variables. Having a super fast system on one end precludes the possibility that system is slowing down the device under test.

Got it.
The 1st attempt was with a 4th gen Core i7 system running Win 7 x64, that would surely be adequate IF I could run DOS or FreeDOS on it 😀
The other option at hand is AMD Opteron 180 which already has Win98SE, I would rather take that instead.

is it only a 10mbit vesa local bus Card ? it doesnt not seem to have any advantage over ISA Cards.
My 3Com Etherlink III is also be able to push nearly 0,9Mbyte/s in both directions/full duplex 10M.

No, AFAIK the BocaLAN card is a true 32bit, 100 mbit card. It is another question whether its beta DOS packet driver is a good baseline for testing or I should run Windows
It just happened that the other computer able to run mTCP has a 10mbit NIC only, and is also only operating at 25x2 Mhz, running the ISA bus under 7.xxx Mhz. So I need a better machine on the other end of as well.

The PCNet-32 chips is only 10BaseT. I wouldn't be surprised if performance is no better than an ISA card. VLBus network cards were never popular and I think the BocaLAN was the only one ever made. If you want decent Ethernet on a 486, go EISA or PCI. You get proper bus mastering and 10/100Mbit support with either one.

SCSI on VLBus is debatable. The Adaptec VL cards don't support L1 writeback caching. I don't know how performance compares, but Adaptec did offer 68pin wide SCSI on their EISA SCSI cards. Both the EISA and VLB cards used the same AIC-7770 series controllers, so it would make a good benchmark comparison. I have Adaptec cards for both buses and a EISA/VL 486, I suppose I should get around to that. 😵

My goal was not to have blazing-fast Ethernet, but to populate all VESA slots with "sensible" cards and have the best speed within the constraints this implies. I am well aware of the limitations, but the motherboard will not operate the 5x86 in WB mode anyway so it is no concern for me. SCSI still means a little less burden on the CPU even for a 486.
To sum up, I have a system that -now- reliably runs at 4x40 Mhz at all tightest timings, all VLB populated, added sound cards etc.
I have never heard or seen this before 😀

Jolaes76,

You've clearly busted the myth .. my VLB setup had just two slots used. I didn't even bother trying to use the third slot given all of the stories at the time.

Back then I was running an ATI Graphics Ultra Pro with 2MB of VRAM and a Buslogic BT-445S SCSI controller. The machine ran OS/2. I still have the same machine but it runs Redhat 6.1 today. I used it for some of the early mTCP debugging work. SCSI is a definite win compared to any other technology at the time. With an operating system that supported it you would get the advantage of tagged command queuing, which dramatically improves the throughput of the drive. (One command at a time is suitable for floppy drive systems, not hard drives ...)

When I do speed testing I always run against a faster machine running Linux. The packet driver is definitely a bottleneck though. By design, a packet driver requires two calls to give a packet to the waiting code; one call to obtain a buffer and the second call to indicate that the buffer has been filled. Sending only requires one call. Things have gotten more advanced over the years, but it's more than adequate for DOS.

Thanks for the feedback everyone, I will see if changing to a Buslogic adapter and installing NT or Linux shows advantage over an ISA NIC. From the scarce info from ancient newsgroups it seems that multitasking is smoother because the NIC accesses memory at 32bit, so transfers are faster when several other devices are active at ISA. Ideally Win 3.11 fwg, but I am not sure about that. Anything MS above that, from Win95 first edition is too slow, I think.

NJRoadfan wrote:

The PCNet-32 chips is only 10BaseT. I wouldn't be surprised if performance is no better than an ISA card. VLBus network cards were never popular and I think the BocaLAN was the only one ever made.

There are other VLB network cards out there, I had one with connectors for three different network types (IIRC, token ring, LAN, and something else). Only 10BaseT though.

As NJRoadfan said, the Bocalan card is 10BaseT as well (my memory failed on that).
However, it seems there can still be a speed advantage over ISA NICs under certain circumstances.

Hello all,

Can you tell me which NIC for VLB w/ 100Mbit were available?

Marco wrote on 2024-04-12, 07:39:

Hello all,

Can you tell me which NIC for VLB w/ 100Mbit were available?

Possibly none 🙁 - Ethernet on VLB

Oh alright thx then