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Springbok
September 12th, 2013, 11:37 AM
15162OK guys,

Apologies for all the questions, but I am hoping that all my questions will eventually help others seeking info on the same subjects.

So I bought the following:

9.1GB IBM SCSI 10K HD

http://www.ebay.com/itm/221271216473

An 80-pin to 50 pin converter

http://www.ebay.com/itm/261216333848

And a Buslogic MCA 32-bit SCSI card (Updated to reflect the single ended version)

http://www.ebay.com/itm/281058996335

Since the IBM 8570 does not provide any way to power the drive, I have a couple of questions.

1) The converter appears to have a 4-pin Molex power plug on it? Could it simply be that I can plug the HD power plug into that. I really hope it is that simple, but probably not right?
2) There is a power port on the left side of the Mobo. From it, there is a power cord running the the speaker. Is there any way to tap into that?

3) Looking at the older buslogic SCSI boards, they used to come with a 4-pin Molex attached. The new revisions do not. The attached pic shows the difference. It looks like I would simply be able to solder a 4-pin Molex on there, but I am not really sure about how to run the wires and it requires me to muck with soldering etc.

I would really like to keep my 8570 as original as possible. The next couple of options will require modding the system, and I would like to avoid that if possible.

4) MCA mafia has instructions on how to mod the disk controller riser to attach a 4-pin molex (see the link below). My question is: I have a free slot on the left side of the riser. Since the HD plugged in the back and the 1.44 floppy plugged in the front, don't have power cables running to them from the riser, I am assuming they are drawing power from their connection to the riser. Is there any sort of adapter I can plug into the free slot that will contain a 4 pin molex?

http://www.mcamafia.de/mcapage0/addpower.htm

5) Lastly... I have security star wrenches, so I can open up the power supply. There must be some way to simply solder wires to the interior works and expose them. I would rather not use this open (unless you tell me it would be best).

Thanks.

dorkbert
September 12th, 2013, 12:13 PM
The HBA you linked to is a BT-646D (HVD) and is missing termination resistor packs. The drive you linked to is Ultra160 LVD. You will want the single-end version (BT-646S). The SCA/50 pin adapter you linked to does not appear to properly terminate the upper 8 bits.

Springbok
September 12th, 2013, 12:32 PM
The SCA/50 pin adapter you linked to does not appear to properly terminate the upper 8 bits.

Dorkbert... can you clarify what that means? Will it not work then? Could you link me to one that will if that is the case?

dorkbert
September 12th, 2013, 12:56 PM
http://www.cs-electronics.com/sca-adapt.htm

What you linked should work, but it leaves some bus signals floating (unconnected) and may cause weird random problems.
Here (http://www.vintage-computer.com/vcforum/showthread.php?37240)'s some past discussion.

Chromedome45
September 12th, 2013, 01:05 PM
Ok this is the one you want: http://www.ebay.com/itm/Future-Domain-MCS-350-Microchannel-Mca-Scsi-Controller-HOST-ADAPTER-/330898338572?pt=LH_DefaultDomain_0&hash=item4d0b13f30c

It is pricey but look carefully it has a 4 pin molex to power the hard drive. The cable from there goes to the SCA adapter.

Or you could get a small power supply that provides +12 & +5 and stick somewhere inside the chassis. Then it will power the Hard drive. I wired the power brick AC side into the onboard power supply AC input on the switched side.

I did something similar when I had my Tandy 2000. See pic.

dorkbert
September 12th, 2013, 01:07 PM
boy, all that work to power a drive. IBM don't making it easy, do they?
can that future domain card supply more than 30w for drive spin up? mind you 19K0613 is a 10k RPM job.

Springbok
September 12th, 2013, 01:22 PM
Dorkbert... so is this what I need then

http://www.ebay.com/itm/80pin-to-50pin-SCSI-Adapter-with-Terminator-/390657600796?pt=LH_DefaultDomain_0&hash=item5af501ed1c

dorkbert
September 12th, 2013, 01:31 PM
... no. ideally you want the adp-9012 or adp-9013. the one you linked appears to terminates the narrow bus (no photo of the component side.)
that or just find yourself a narrow SCSI drive and forgo all this adapter pain... one other thing, SCA drives are generally unterminated, if that drive is the only device on the bus, you will want an adapter that can terminate the entire width of the bus.

here (http://www.ebay.com/itm/151104870185)'s a 9 GB narrow dirve.

Springbok
September 13th, 2013, 03:37 AM
Hey Guys,

This link shows the 8570 planar details. At J10

http://ohlandl.ipv7.net/8570/8570_Reply_OEM.html

In the doc it states

J10 3 pin header (power for IDE drive?)

and

J10 Power header for IDE drive (YES!!!). From left to right (power connector edgecard towards CPU) +5v, 12V, GND

Anyone know if this means I can get one of these to power the SCSI drive (and of so which one in the list)

http://www.ebay.com/sch/i.html?_odkw=4+pin+molex+fan&_sop=10&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.X4+pin+molex+ 3&_nkw=4+pin+molex+3&_sacat=0

thanks.

krebizfan
September 13th, 2013, 09:01 AM
First off, that is a replacement motherboard. The IBM 486 motherboard looks like http://stason.org/TULARC/pc/motherboards/I/IBM-CORPORATION-486-PS-2-MODEL-70-486-25.html Fewer features. The 3-pin header is more often used to power a fan and note J10 is close to the CPU and with a 486-66 in that cramped case it needs it.

You would be better off connecting to the power supply cables with a splitter if you have to. Motherboard power connectors don't supply anywhere near as much power.

Springbok
September 13th, 2013, 10:20 AM
First off, that is a replacement motherboard. The IBM 486 motherboard looks like http://stason.org/TULARC/pc/motherboards/I/IBM-CORPORATION-486-PS-2-MODEL-70-486-25.html Fewer features. The 3-pin header is more often used to power a fan and note J10 is close to the CPU and with a 486-66 in that cramped case it needs it.

You would be better off connecting to the power supply cables with a splitter if you have to. Motherboard power connectors don't supply anywhere near as much power.

Yeah... I ordered some PCB 4-pin Molex L brackets. It looks like it will fit right in the power slot at the top of the SCSI card I bought.