Is that 386 motherboard especially terrible? Truly underwhelming performance.

gdjacobs wrote:

Is that 386 motherboard especially terrible? Truly underwhelming performance.

386 cpu just downclocked to 25mhz to compare with 286

Aha, and it is an SX as well. That explains the NSSI drystone result.

gdjacobs wrote:

Aha, and it is an SX as well. That explains the NSSI drystone result.

Results in some tests look too low anyway. Either the 286 is much faster than typical 286 on this Hz, or 386 SX is not good.

EKb's 286-25 is probably best scenario for a 286. Hats off to him its probably the fastest 286 ever built!

Here's a 286-16 that is not too impressive:
http://www.ebay.com/itm/286-motherboard-AMD-N … TgAAOSwJb9WqeIH

It scores 3234 Dhrystones on CheckIt. It could be that this is Turbo off result, but usually the best 286-16's score around 4000 Dhrystones (Checkit, NSSI) and without Turbo those systems are around 2600 Dhrystones, depending on the motherboard. In the 286 world it seems you can find really well tuned, average and low performance boards at the same clock. My M219 286 board performance is horrendous.

This one seems to be not too well performing too even for a 286-12:
http://www.ebay.com/itm/Vintage-286-motherboa … 2AAAOSwpzdWqeDI

Only 2240 Dhrystones and it seems to have Turbo on. A best case scenario for a 286-12 would be close to 3000 Dhrystones i guess?

carlostex wrote:

286-12...Only 2240 Dhrystones and it seems to have Turbo on.

Unfortunately, it's slow. Probably just 1WS.
For example, if my mobo with 6374 dhrystones divide by 2, get up to 3150 dhrystones for 12,5mhz

Tertz wrote:

gdjacobs wrote:

Aha, and it is an SX as well. That explains the NSSI drystone result.

Results in some tests look too low anyway. Either the 286 is much faster than typical 286 on this Hz, or 386 SX is not good.

286 @25Mhz runs ISA bus quite high (around 12MHz). I guess even memory speed is effected by it. But usually you can compare raw cpu speed - drystones.

carlostex wrote:

its probably the fastest 286 ever built!

Speed Test has stats of a little faster 286.

Nocito87 on YouTube had some insight when talking about his Highscreen 286-16mhz vs a 386. I must quote him:

It is definitely faster than a 386SX16, but that is a known fact. I don't know exactly why. There are multiple explanations for that. The best explanation I heard is that the 386SX has a 32bit internal microarchitecture with a 32bit prefetch queue but still just a 16bit databus. On a 286 there are 2 bytes loaded to the preftech qeue from ram and sent to the databus. On a 386 there are 4 bytes loaded to the preftech qeue, which can't be sent to a 16bit databus. So the 386SX has to make two 16bit accesses before it can load the next 4 bytes from ram, which also needs two accesses. I don't know if that is 100% correct, but benchmarks prove that a 286 is a bit faster than a 386SX with same clock speed. But a 386SX is able to execute programes and games designed for the 32bit core microarchitecture.

https://youtu.be/S_ZEWvokp3o

A fast 286 with a good motherboard can outpace a 386 in 16-bit applications just because of the architectural differences. 286s came out at a time where they weren't fully utilized before the software techniques of the 386/486 era caught up to them.

....My 286 12mhz is slow as crap though.

johnnynismo wrote:

A fast 286 with a good motherboard can outpace a 386 in 16-bit applications just because of the architectural differences.

Late 386SX seem close to best 286 in performance per Hz. 386SX 16 MHz were early models mostly.

johnnynismo wrote:

https://youtu.be/S_ZEWvokp3o

A fast 286 with a good motherboard can outpace a 386 in 16-bit applications just because of the architectural differences. 286s came out at a time where they weren't fully utilized before the software techniques of the 386/486 era caught up to them.

from youtube screenshot in time 1:47:00

Stunningly! this is almost my result on my mobo with VLSI, when previously worked at 16MHz.
In my CheckIt 3.0 = 4020 dhrystones (16mhz)

6.4 with SpeedStar 24X, 1mb
6.8 with CL5420 512kb on my mobo with VLSI (16mhz)

This is possible due to the difference of speed ISA 🙁

Nocito87's (from youtube) mobo 286:

Tertz wrote:

johnnynismo wrote:

A fast 286 with a good motherboard can outpace a 386 in 16-bit applications just because of the architectural differences.

Late 386SX seem close to best 286 in performance per Hz. 386SX 16 MHz were early models mostly.

Yes, I'm 25+ years late hahaha! TBH I'm learning a lot about these older systems. I have a Turbo XT 8088-2 8Mhz clone from 1987 when I was 5yo to 1997 when my dad bought a P200MMX Sony Vaio PCV-120. I missed out on EVERYTHING in between.

Over the last few months I've found two 386s, a 486, Socket 5 Pentium, Socket 7 Pentium and Cyrix MII, Pentium 2, and Pentium 3 machines and a lot of other retro sound and graphics hardware. I'm playing catch-up.

Performance comparison of CPU: SuperFast-286-25 and AMD-386SX-25-Overclocked

System 1: 286-25mhz

Clocker in 25mhz (100/4=25mhz)
Mobo = Noname with five chips VLSI
CPU = Harris 25mhz.
FPU = Intel 287XL
RAM = only DIP20 Siemens 60ns(super faster) + Aluminium cooler
Cache = No
VGA = CirrusLogic 5420, 512kb, Jump JP1=Closed (for low wait state)
Sound = ESS1868
Multi I/O = Chips "TANS" (china?) for fast speed ISA.
HDD = CompactFlash 1GB, with Ontrack

For more information see here: Kixs's 286 to the Max

286 BIOS default:

System 2: 386SX-25mhz

Clocker in 25mhz (50/2=25mhz)
Mobo = 303n1
CPU = AMD 386SX-40
FPU = IIT 3c87SX-33
RAM = 2x4mb=8mb, 60ns SIMM30
Cache = No
VGA = CirrusLogic 5420, 512kb, Jump JP1=Closed (for low wait state)
Sound = No
Multi I/O = Chip GoldStar Prime 2 (not "2C")
HDD = Quantum Fireball AT 6.4, with Ontrack

386 BIOS is Overclocked:

AutoBios: Memory performance - Fast
to overclocked: Memory performance - Fastest

WARNING: Left only 286-25. Right only 386SX-25 + overclocked.

3D Benchmark:

3Dbench 1.0:

286 = 10.4 fps. Best.
386 = 6.7 fps.

3Dbench 2.0:

286 = 10.4 fps. Best.
386 = Error calculating. Value < 7.0 = overflow.

Formula One Benchmark 1:

286 = 102% load. Best.
386 = 151% load.

Formula One Benchmark 2:

286 = 316% load.
386 = ___% load.

Wolf 3D. PC Speaker (NOT SoundBlaster) + Mouse + FullScreen

286 = 19.3 fps. Best.
386 = 12.2 fps.

3DSpace:

286 = 15%. Best.
386 = 12%.

Morph3D:

286 = 79.0 fps. Best.
386 = 61.5 fps.
.
.
.
.
CPU Benchmark:

Landmark 2.0:

Landmark 6.0:

Checkit 3.0

Norton SysInfo 6.0:

286 = 19.4 XTs. Best.
386 = 12.3 XTs.

PC-Tools SysInfo 9.0:

286 = 15.1 XTs. Best.
386 = 10.3 XTs.

NSSI 60

DoctorHard 3.7:

PC Doctor 1.7:

286 = 6.9 MIPS and Read 16bit = 11mb/s. Best
386 = 5.2 MIPS and Read 16bit = 6mb/s

PC_info 4.04:

286 = 18.1 XTs. Best.
386 = 12.4 XTs.

FPU Benchmark:

Fbench:

287XL =
IIT387 = Best

CABT:

287XL = 6.26 sec.
IIT387 = 3.13 sec. Best

FLOPS:

287XL = 0.04 MFLOPS.
IIT387 = 0.12 MFLOPS. Best

RAM Benchmark:

SST (sorry only 386+)

286: Memory________Failed
386: Memory________R=10 MB/s______W=18.5 MB/s_____Move=12 MB/s

SysTest:

286 = 12mb/s, 0WS.
386 = 5,2mb/s, 1WS

HDD <-> ISA Benchmark:

CheckIt 3.0:

286 = 2774 kb/s. Best.
386 = 1765 kb/s.

OTHER Benchmark:

TopBench:

286 = Score 69. Best.
386 = Score 48

hello
i am just interested in that your 286 board's bios can handle a 1gb hdd drive, i thought they can handle 512mb max.
is it just up to a board with modern version of bios, or something? and have you tried the largest hdd that it can handle?

unfortunately, it is old BIOS. max to 508mb.
For more than 500mb required overlay program Ontrack 8.0 or 7.0
http://old-dos.ru/index.php?page=files&mode=f … &do=show&id=889

On the 286-25, what speed is the FPU running at? It seems to be underperforming pretty badly compared to the IIT on the 386SX.

Also, somebody mentioned the ISA bus is running at 12.5MHz. How is that determined? From what I have seen, very late 286s have ISA dividers in the BIOS setup like on 386 boards.

See my thread about 287 fpus on different mobos.
Kixs's 286 to the Max

I'd guess the 387 runs at full speed @25MHz, while 287 uses dividers (3 or 2). There are some information out there to suggest that later 287 fpus would internaly multiply by some factor to negate this. But I'm not sure if that's true.

I have two very late 286 with 386 look AMI bios and doesn't have any ISA dividers. My 386SX boards with AMI bios and even some early 386DX bios doesn't have it too.

I am pretty sure it is true that 287XL CPUs have a 3/2X multiplier to undo the 2/3X multipliers common on early 286 boards. I own a retail 287XL in box and I should check the documentation.
I remember the PCChips 20MHz M209 motherboard I had was set to a FPU 1/2X multiplier by default, and I think it was adjustable to either 2/3X or 1X. I guess the FPUs rated for 20MHz operation were somewhat uncommon, and the manufacturer assumed many people would be using older i287 parts.
I believe the M209 board I had used a 1991 core AMI BIOS, and I do seem to recall that one had adjustable ISA dividers. Some of the boards that didn't have the divider in the BIOS allow you to set it using a jumper on the motherboard.

Ekb wrote:

unfortunately, it is old BIOS. max to 508mb.
For more than 500mb required overlay program Ontrack 8.0 or 7.0
http://old-dos.ru/index.php?page=files&mode=f … &do=show&id=889

but your picture showed that the 286 bios displaying 977mb, does that work?

This 286 bios (and 386-486), line "User Type" can be up to 8gb, but it only works up to 504mb, and the rest will errors "Sector not found"

__________Sector_______Head_______Cylinder__________Size
IDE________255__________16________65536__________127500mb
BIOS_______63__________256________1024___________8064mb
Result______63___________16________1024___________504mb

P.S. this 286 bios is not patched.