douglar wrote on 2024-01-25, 23:55:

b0by007 wrote on 2024-01-25, 21:40:

No addon controller or drive overlay. The bios just detects and uses full hdd up to 4gb.

It looks like you might have a newer Bios version than the original poster. Bios with support for P24t processors didnt come out until Q4 1995.

Not really. I posted a screenshot where you can see is bios v. 04.04.
I used a normal 486 dx2 66 mhz processor. I get an warning error bios message becouse I dont have conected the original fan. I use a molex fan.
If you switch on dipswitch 8 (where it say SIEMENS), you can use normal processor up to dx2 66mhz.
There is another undocumented setting, if you set dipswitches MHZ-1 and MHZ-2 both to ON, bios will show 8 mhz, but performance test and cpucheck will show 40mhz bus speed.
At page 135 is the manual for these models.

edit: actually I made two videos about this HP Vectra 486/25N. You can check it out at my youtube page: https://www.youtube.com/watch?v=1uqdm6FulsE

LaC wrote on 2024-01-25, 18:08:

konc wrote on 2024-01-25, 17:21:

LaC wrote on 2024-01-25, 06:55:

I tried hooking it up to my modern PC and the drive still won't read.
So guess I need to replace this 30+ year old drive. Sad.

How did you connect it to your modern PC? If it's with some USB -> IDE adapter, don't throw away the drive yet.

Yes usb->ide adapter.
I'm sure the data is fine on the drive, but I suspect its the motor or something on the main board.

I've yet to see such an adapter that works with pre-LBA drives.
I'm not trying to say that the drive is OK, but that you haven't properly tested it yet. Most probably it doesn't work with the adapter, try to check it in a machine with IDE to ensure it has failed.

b0by007 wrote on 2024-01-26, 10:07:

Not really. I posted a screenshot where you can see is bios v. 04.04. I used a normal 486 dx2 66 mhz processor. I get an warning […]
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Not really. I posted a screenshot where you can see is bios v. 04.04.
I used a normal 486 dx2 66 mhz processor. I get an warning error bios message becouse I dont have conected the original fan. I use a molex fan.
If you switch on dipswitch 8 (where it say SIEMENS), you can use normal processor up to dx2 66mhz.
There is another undocumented setting, if you set dipswitches MHZ-1 and MHZ-2 both to ON, bios will show 8 mhz, but performance test and cpucheck will show 40mhz bus speed.
At page 135 is the manual for these models.

Very interesting. It's always nice when something works unexpectedly.

LaC wrote on 2024-01-26, 04:10:

Sudos wrote on 2024-01-25, 23:22:

I wouldn't bother trying to resurrect the drive, assume it has failed. Prodrives are notorious for having rubber head bumpstops. It's likely it hit it and got stuck. Goopy mess, can be replaced with some heat shrink if you're quick about it and the platters didn't get any on them however.

its still spinning. you can hear the head try to read when it boots up per normal. It's just loud.

Doesn't matter, they still have that issue and it's a whole mess, speaking from personal experience. If you want prolonged use, you're gonna want to fix that.
Also, you may wanna post a pic of the drive's board as well so that can be ruled out as your issue as well.

Sudos wrote on 2024-01-26, 15:41:

LaC wrote on 2024-01-26, 04:10:

Sudos wrote on 2024-01-25, 23:22:

I wouldn't bother trying to resurrect the drive, assume it has failed. Prodrives are notorious for having rubber head bumpstops. It's likely it hit it and got stuck. Goopy mess, can be replaced with some heat shrink if you're quick about it and the platters didn't get any on them however.

its still spinning. you can hear the head try to read when it boots up per normal. It's just loud.

Doesn't matter, they still have that issue and it's a whole mess, speaking from personal experience. If you want prolonged use, you're gonna want to fix that.
Also, you may wanna post a pic of the drive's board as well so that can be ruled out as your issue as well.

Here is a pic of the board.

LaC wrote on 2024-01-27, 23:42:

Here is a pic of the board. https://i.imgur.com/ePD18IA.png […]
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Here is a pic of the board.

Yep, looks fine to me, so I think what definitely happened is your rubber bump stop is preventing the drive from seeking.

This is the rubber bumpstop in question next to the butt-end of the head swingarm.
According to http://www.asterontech.com/Asterontech/Quantu … 0s_Restore.html there's two per drive, one at each extreme end. With a steady hand and a dust-free environment (Outdoors in winter, ideally, with snow on the ground, if a makeshift clean room cannot be obtained, and this will also have the added benefit of keeping most of the rubber goo together due to a low temperature) you can supposedly use stacked o-rings to fix the issue. Of course this is only worth it assuming the drive had no bad sectors to start and you want to seriously save the drive.

If this is too much work, you can replace it with a 256MB IDE DiskOnModule from eBay or the like without too much in the way of trouble. the machine will be quiet and chatter-free, yes, but it will be wildly more reliable in the long run. a head stuck to a rubber bump stop will spin up and identify and try to seek but the added gunk will cause seek issues and can also mess the balance of the head up enough to cause problems in some extreme cases.

your best bet is to get the drive open first and see what you're really working with, just know that this definitely can be destructive, and you should be using JIS bits and not Philips bits to get the drive open as well, but sometimes they take well to a #2 Philips if you're in a pinch, just not always.

Another thing that may have happened is your head caught a flake off the neodymiums, as they're old enough now that the coating is coming off. if you take a look at that drive, there's definitely a lot of flakes on the 40MB drive there. it's entirely possible.