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Dell OptiPlex GXa won't boot; how to configure devices in SCSI BIOS

I checked the jumper pins on the hard drive. All jumper pins have no jumpers. Among other things, that means that the HDD SCSI device number is already set to 0, matching the SCSI BIOS.

I remember that in the early days, there was nothing in the motherboard BIOS about CD-ROM drives. One would simply attach the CD-ROM drive to the IDE cable (setting master/slave as appropriate), then get DOS to load the CD-ROM driver and MSCDEX.

I see now that I definitely misspoke earlier; the CD drive is not connected to the motherboard. The CD drive is connected to the SCSI card via a ribbon cable with many more wires than 34. The device connections go like this. I had to diagram it because there are so many native cables in the case that taking a good picture is impossible.
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Any change if you detach the SCSI cable (at the controller)? Expected would be a scan result that only shows the SCSI card.

Disconnecting the 2 internal SCSI cables from the SCSI card and doing the scan via SCSI Disk Utilities results in the same response: the computer hangs up and I have to push reset.

Here is a picture of the SCSI card with both internal cables disconnected.
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Here is the SCSI card user manual:
http://download.adaptec.com/pdfs/user_guides/aha2940u2w_ur.pdf

Here is a troubleshooting article at IBM that has been helping a lot.
https://www.ibm.com/support/pages/troubleshooting-adaptec-scsi-issues
 

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Looking more at "Host Adapter Configuration Error":

It does not appear in the AHA-2940U2W manual.

---------------------------------------------------------------------------

On the Adaptec web site, 'Answer ID 847', at [here] contains, in part:

2940U2W shows 'Host Adapter Configuration Error' at boot with DLT tape library attached.
This message does not occur when DLT tape library is disconnected
.

Related to that, I saw other discussions of 'Host Adapter Configuration Error' for Adaptec cards, talking about incompatible devices on the SCSI bus.

Because you still see 'Host Adapter Configuration Error' when all SCSI cables are removed from the card, an incompatible SCSI device (or termination, etc.) cannot be the cause of your problem.

---------------------------------------------------------------------------

Appearing in the manual for some other Adaptec SCSI cards is:

Host adapter configuration error.
The motherboard BIOS did not assign an IRQ to the host adapter.
Run the CMOS Setup program and check the IRQ assignments
.

And whether it is related or not, at [here] is: "All Adaptec's PCI SCSI controllers require a bus mastering PCI slot (except the 2920 / 2920A)."

---------------------------------------------------------------------------
 
I should add that today, I'm running a Quantum DLT4000 on an Adaptec AHA2940U2W. No issues. Even though it's SE, the AHA29160 tests to see that it's properly terminated and warns if it doesn't see a terminator.
 
The 2920 is really a Future Domain TMC1600, re-badged when Adaptec acquired FD. Got one of those that has the FD logo but runs with the 2920 drivers.
 
Appearing in the manual for some other Adaptec SCSI cards is:

Host adapter configuration error.
The motherboard BIOS did not assign an IRQ to the host adapter.
Run the CMOS Setup program and check the IRQ assignments
.

And whether it is related or not, at [here] is: "All Adaptec's PCI SCSI controllers require a bus mastering PCI slot (except the 2920 / 2920A)."

Now it looks like we are really getting somewhere toward the root cause.

Here is the service manual for the Dell OptiPlex GXa.
https://www.manualslib.com/manual/35...?page=3#manual

Page 1-3 of the service manual has this to say about bus-mastering. It's the only time it mentions it.
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The Adaptec SCSI card is plugged into PCI slot 1. There are no other PCI slots occupied. There are 3 ISA slots; none are occupied.

Here is a log file I created using CheckIt 3.0. It tells what is seen on the IRQs and DMAs. (EXPLOSIV.COM is a TSR DOS screensaver I have on the floppy disk.)
CHECKIT.LOG.txt
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Page 1-15 of the service manual says these below are the IRQ and DMA assignments of the computer:

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Is there some requirement from post #22 that is not being met?

Is there an IRQ or DMA conflict shown here that I am not seeing?

Page 4 of the SCSI card manual is the troubleshooting section. Could any of these items apply?

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I think I've narrowed it down to these 3 that I've marked with "?".
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Post #22 said:
Host adapter configuration error.
The motherboard BIOS did not assign an IRQ to the host adapter.
Run the CMOS Setup program and check the IRQ assignments
.

How do I make the system BIOS assign an IRQ?
 

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I have little PCI experience, apart from plugging in PCI cards. Mostly, plug it in and it works.

I think I've narrowed it down to these 3 that I've marked with "?".
#1: If a motherboard's PCI version is later than 1.0, it's information that surely, we'd expect to see in the motherboard's manual/specs. So, could this be the cause!
#2: I have experienced that myself. Eliminated because you have no ISA cards fitted.
#3: Appendix A of the Dell OptiPlex GXa's manual shows no motherboard SETUP functionality to manually assign interrupts to PCI cards.

Is there an IRQ or DMA conflict shown here that I am not seeing?
With your only card/s being PCI, I expect that the motherboard will ensure that there are no conflicts.
 
#1: If a motherboard's PCI version is later than 1.0, it's information that surely, we'd expect to see in the motherboard's manual/specs. So, could this be the cause!

Table 1-5 from page 1-27 of the OptiPlex GXa service manual says the PCI version is 2.1, so it meets that.
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#3: Appendix A of the Dell OptiPlex GXa's manual shows no motherboard SETUP functionality to manually assign interrupts to PCI cards.
With your only card/s being PCI, I expect that the motherboard will ensure that there are no conflicts.

The service manual says the same motherboard is used for all 3 submodels of the OptiPlex GXa (low profile, high profile, mini-tower). Here are the motherboard settings. They tell nothing about IRQs.
https://stason.org/TULARC/pc/motherb...IPLEX-GXA.html

The situation seems to be that the SCSI card isn't assigned an IRQ automatically by the system BIOS, and I can't find a way to manually do it. I'm stumped about how to proceed. Anyone, please help.
 
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PCI is very different from ISA. Interrupts are negotiated and often shared. DMA is busmaster-type, not 8237 ISA type. The GXa is a PII system with Intel 440LX chipset--both known workhorse items.

The AHA-2940 family is legendary for reliability in all of its forms (that includes the 3940). My suspicion is that there's a configuration issue with your drive and not with the controller (cable? terminator?). I routinely use 2940s on P1, P3, P4, Socket 754, Socket 939,, P4, Socket A, AM2 and AM3+ (I'm probably forgetting a few) hosts with no issue.

If this were my system, I'd first load the system up with the EZ-SCSI (version 4) tools to see what is being seen. I'd also try a different drive and cable. Seems to me that you guys are making entirely too much of this.
 
My suspicion is that there's a configuration issue with your drive and not with the controller (cable? terminator?).

I don't think the problem is with the cable or terminator either. The hard drive has jumper pins for configuring it. See post #21. The hard drive manual is at this link. The jumper pin header is shown on page 3-7. Nothing seems out of place to me.
https://www.manualslib.com/manual/46...page=33#manual

If this were my system, I'd first load the system up with the EZ-SCSI (version 4) tools to see what is being seen. I'd also try a different drive and cable. Seems to me that you guys are making entirely too much of this.

It is possible that the hard drive is simply bad. It has sounded fine but it could be bad. I will look for some other SCSI hard drives as candidates to try.

Thanks; I hadn't heard of EZ-SCSI before. I found EZ-SCSI and put it on a floppy. I'll try it as soon as I get a hard drive working; it only runs under Windows (95 or later, I assume).

As soon as the computer will turn on. This computer has a habit of not turning on sometimes. Then I can come back hours later and it will turn on. Nothing has changed except the passing of time. :|
 
My copy of EZ-SCSI is on CD, so there's a bit more to it than what fits on a floppy. It includes DOS-mode ASPI drivers for most Adaptec/Trantor SCSI cards. (BTW, ASPI is what you want to figure out what's connected).

I assume that you're using the 28-pin option connector toward the front of the drive and not the 12-pin one on the rear. The manual is a bit confusing in the it says that jumpering an ID pin to ground renders the corresponding ID bit zero, which is the opposite of the way most SCSI drive jumpers work. So there should be no jumpers on 1,2,3 and 4. I'd also add a jumper between 27 and 28. There should be no other jumpers present on the 28 pin J3 and the 12-pin rear option connector.

If you still get errors, try putting jumpers on 1-2, 3-4, 5-6 and 7-8, just in case the manual is wrong.
 
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My copy of EZ-SCSI is on CD, so there's a bit more to it than what fits on a floppy. It includes DOS-mode ASPI drivers for most Adaptec/Trantor SCSI cards. (BTW, ASPI is what you want to figure out what's connected).

Yes, I see there is a >300 MB. edition of version 4.01, but I need the CD drive to be operable to use that one. Even getting the hard drive up doesn't imply that the CD drive would be usable yet. Or I can use the USB ports!

So there should be no jumpers on 1,2,3 and 4. I'd also add a jumper between 27 and 28. There should be no other jumpers present on the 28 pin J3 and the 12-pin rear option connector.

There are currently no jumpers on either the 12-pin rear set or the 28-pin option header set. From the hard drive manual, 27-28 is for TERMPWR:

"3.4.2.6. SCSI Bus Termination Power Jumper. The TERMPWR jumper enables the active termination circuit to receive power from an external host when installed."

Does that mean the SCSI terminator might not currently have power? Could that be preventing the SCSI card from working?
 
It's been a while since I've had a SCSI setup but I do remember one of my SCSI controllers had a setup program that walked you through and showed where the present terminations where. IIRC, IRQ's where never an issue. You simply set the device ID and that was it. I would be checking the the cabling and the SCSI drive jumpers.
 
You might need to run the Dell ISA configuration utility on that system. It could be reserving IRQ for the ISA bus for things that are no longer installed.
 
Supplying termination power by the peripheral and the controller is not verboten in the SCSI world. Both use diodes, so no possibility of conflict. I enable termpower on my devices just in case my controller doesn't provide it.
 
Sattinger's Law strikes again!

The power supply was not completely plugged into the motherboard. I thought I had pressed it in all the way when I was first examining it, but apparently I didn't. With a screwdriver, I was able to reach through the nest of cables and wires and push it in the rest of the way and the computer boots normally now.

Not only that, but the SCSI BIOS behaves normally now too! Whoo hoo!

Yet all is still not well.

There were 2 independent problems. One was the power supply not being fully connected to the motherboard. Because the power supply evidently only powers up if under load from the motherboard, there was no reaction to turning the computer on.

The second problem, the plague of the SCSI BIOS, turns out to have been just a bad hard drive. The HDD that came with this case is a Quantum Atlas 10K III 3.5 series SCSI HDD. It spins up but apparently is no longer good.

I found a Seagate ST39140W SCSI HDD, 9.1 GB., and attached it. The SCSI BIOS now behaves as expected and scans the SCSI devices properly.
https://stason.org/TULARC/pc/hard-dr...LTRA-SC-W.html

The Seagate does register in the SCSI BIOS scan (and the computer no longer hangs up when trying to do that scan), and I am able to set it as device 0, but the boot process gives an error for it: "Start unit request failed." The drive does make unusual sounds while trying to initialize. I suppose I just need another assumed-good SCSI HDD to try.

The CD drive likewise does register with the SCSI BIOS, but I'm unable to switch to it after booting. The boot device I am using is a 1.44 MB. floppy with MS-DOS 6.22.

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Are you looking for a 5.25" full-height, or 3.5" or 5.25" drive?

As far as the SCSI CD, if you're accessing it in DOS, you need the ASPI driver for the card and then the ASPICD.SYS driver on top of that (hint: EZ-SCSI has them). If you're running NT, it should have the correct drivers present in the installation CD.
 
I like the Seagate 3.5" drives. Be aware that many of them come in SCA-connector-type and you'll either need an SCA cable or an adapter. Also, be aware that many of the server-grade ones are full-height 3.5" form factor (1 5/8" tall) rather than the more usual 1.0" height.
 
Any advice on the second SCSI hard drive or the CD drive to get them working correctly?
Re the ST39140W hard drive.

The 'Common Error Messages' section of the AHA-2940U2W manual, suggests for the error of 'Start unit request failed', "Run SCSISelect and disable the Send Start Unit Command for the peripheral".

That may be related to the final sentence in the following, found online:
"Send Start Unit Command - When set to Yes, sends the Start Unit Command to the SCSI peripheral at bootup. Enabling this option reduces the load on your computer's power supply by allowing the SCSI bus to turn on SCSI peripherals one-at-a-time when the computer boots. Otherwise, all SCSI peripherals turn on at the same time. Most peripherals require you to set a jumper before they can respond to this command."
 
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