Stojke wrote:

Hey guys, i have a questions. […]
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Hey guys, i have a questions.

I am building an 486 DX system with the following (current) components:

Motherboard - Unknown model > Symphony chipset 6X ISA / 2X ISA+VLB / 30PIN SIMM 32MB MAX / 256kB CACHE 1MB MAX (Made in USA)
CPU - 33MHz DX CPU (Thinking of using AMD DX2 66MHz, or if found DX 50MHz)
RAM - 16MB 50ns (Thinking of using 32MB 60ns)
VGA - Tseng Labs 4000ET
AUDIO - I don't know, i will use a little bit of this and that, thinking of using Crystal CS4236B for a while

And now the main question - I want to use SCSI disk and CD ROM in this thing, so i got my self some controllers.
They are:
1. Tekram DC-300B (Has 256k x 16 cache chip)
2. Adaptec - AHA1542CF
3. Adaptec - AHA1420B

The disks i have are IBM UltraStar models 2x4GB and 1x2GB.
I know that transfer speed in the ISA bus is limited and having cache would probably give better performance, but Adaptec models are very good also. But i am not sure of small detail differences between them since i couldn't find an Tekram manual.

I am planning of getting an cool VLB Tekram DC-800 controller one day, or some other maybe (16MB CACHE - My 50ns RAM modules would come in handy here), and some VLB VGA card as well, maybe ET4000 W32P.
But for now i want to use what i have.

Misconception: drive cache makes drives faster. While partially true, it should be noted that drive cache makes SLOW drives faster. If you snag a newer drive (i.e. ultra 160) cache is not going to make ANY difference. Also cache only really helps in writing, very little in reading.

the adaptec 1542cf is the defacto isa controller.

adaptec makes a VLB card, I know they are on ebay constantly and are relatively cheap. VLB is always going to be faster than IDE. That said, If you are going to just play games, I'd say stick with the 1542. Save your vlb bandwidth for video.

Nice! A symphony board with a VLB chipset. I've always wanted one of these because I'm so impressed with the performance of my ISA only model. Who makes your board? Is it a Young Micro?

@ Luckybob

I see, so both VLB cards would share the same bandwidth? Hmm...
Guess i will go with AHA-1542CF than 😀

What i am also wondering is the Controller speeds. All of mine hard drives are 20Mb/s, but ive only ever seen them operate at ~1500kb/s (In MHDD), regardless of using an ISA controller or an AMD PC SCSI Vectra PCI controller. I am still to run a few more tests to be sure (downloaded some retro bench programs).

@ Anon Coward

I also read somewhere that they are OK 😀
Here is an image of mine: Click on meh

The only sticker on the board (not counting BIOS sticker) only has the serial number:
S/N 9316290

On all the CHIPSET chips it says MADE IN JAPAN.

I can not start it because all my PSUs are in the basement.

Ah, that's the Young Micro. I once had one of these boards, but it was bad. I wanted to try to repair it, but I did an international move and didn't have room for everything so it went to hardware heaven.

It's pretty crazy that this board supports 1024kb cache. It's a pretty rare option for a board of that vintage. Perhaps the earliest I've ever seen.

Do you have any suggestion on how should i diagnose/test the board?
I dont have any VLB Graphics cards, except one Trident whos one capacitor is broken off.
I also have 9x W24257AK-15 Cache.

---

Been searching for my model, found this:

1VS486F-3VL Motherboard
2
3        - AMIBIOS ID string  40-0700-006259-00101111-111192-SYMP-F
4        - 8-30 pin SIMM slots    (1-32meg FPM DRAM)
5        - 3-32bit VESA Local Bus slots
6        - 8-16bit ISA slots
7        - 64k-1024k CACHE support in 8-32pin sockets + 1 TAG RAM socket
8        - AMI BIOS American Megatrends 486DX
9        - Symphony Chipset (MB-SYP243LV-V12)
10        - ZIF 3 CPU socket which supports these processors:
11          INTEL 80486SX/DX/DX2, ODP586SX
12        - Supports speeds of 25/33/40/50/66 MHz.
13        - manufactured by: Young Micro Systems Inc.
14
15
16VS486G-3VL Motherboard
17
18        - BIOS ID string  40-2800-006259-00111111-121593-SYM   WAG-H
19        - 4-72 pin SIMM slots    (1-128meg FPM DRAM)
20        - 3-32bit VESA Local Bus slots
21        - 8-16bit ISA slots
22        - 64k-1024k CACHE support in 8-32pin sockets + 2 TAG RAM socket
23        - AMI / Phoenix 1993 BIOS
24        - Symphony SL82C491 & SL82C492 Chipset
25        - DALLAS realtime clock
26        - ZIF 3 CPU socket which supports these processors:
27          INTEL 80486SX/DX/DX2, P24C,P24D,P24T
28          CYRIX CXM6,CXM7
29          AMD AM486SX/DX
30        - Supports speeds of 25/33/40/50/66 MHz.
31        - manufactured by: Young Micro Systems Inc.

But my CHIPSETs are
SYMPHONY SL82C461 and SL82C362
With another small chip: SYMPHONY SL82C465
It also has an PALCE16V8H-15PC/4

You could always solder the capacitor back on, use an ISA graphics card, or buy another VLB.

Its one of those in an hard plastic/ceramic casing, an its completely smashed. Only pins are standing 😁

It's a tantalum capacitor. I believe it should be 10uf 16V.

I have a DPT PM2021 ISA card I used with my 486 66 that was built to run NEXTSTEP for Intel. I kept it in the system as I upgraded to 5x86 and ran Windows 95. Worked just fine.

I am rebuilding that config and will be using the DPT card (which I still have) to handled the drives and CD-ROM.

Here's the board:

http://www.flickr.com/photos/35448539@N00/396 … hotolist-73pShM

bp

For what it's worth, we idnetified your board:
https://theretroweb.com/motherboards/s/young- … t-vega-486f-2vl

I have added the potato field picture, if you still have the board, front/back pictures and a bios dump would be welcome.

DPT is by far a good choice, it can be upgraded with cache and RAID modules.
Used an EISA DPT SCSI in one of my 486 builds before.
The AHA 2842 is the VLB card mentioned before.
Due to the board having two VLB slots it would be a good chhoice, if you can grep one for cheap.

Just keep in mind that graphic cards can be overclocked more easy by running the VLB at 40MHz or even faster.
HDD controllers tend to data corruption attached to an overclocked VLB.