[shae]

Am I correct in assuming I can run a 160GB HDD with Win98 and no BIOS support (which detects it as 8GB) as long as just don't use areas >137GB?

It's the BIOS part I'm not sure about. Does it matter for anything other than DOS? Is booting affected? The boot partition is 2GB, so it falls within the 8GB detected by the BIOS.

[submix8c]

What's the MoBo Make/Model (you didn't say)? There are "patched" BIOS for some older ones (not TOO old).

You could use a HDD DDO (Dynamic Disk Overlay) from the Manufacturer (you didn't say what Make/Model of it either).

This post has been edited by submix8c: 30 August 2012 - 11:44 AM

[shae]

The mobo is ASUS P2B, the HDD is a WD AAJB. But I don't want custom BIOSes or anything exotic, and I don't care about DOS as long as Win98 can boot the drive correctly.

Beyond booting I'm already using something similar: a 500GB external drive with the initial ~128GB as FAT and the rest NTFS. I just don't know if booting might be affected by the BIOS misidentification.

[submix8c]

Highest BIOS (haven't tried the links):
http://www.wimsbios....topic10054.html
Appears that a 32/64GB limit exists (maybe 120gb)?
No "custom" BIOS for it.

Do you understand DDO? Vendors of Hard Disks supply a SOFTWARE work-around for use on boards that don't support it. These do the job JUST FINE!

There are various versions of the ASUS P2B - which ONE?
What SPECIFICALLY is the HDD.
You're answers are NOT specific.

Have you actually used the External HDD on it? IOW, does it HAVE a "controller" in the enclosure (which BYPASSES the BIOS)?

THEORETICALLY, as long as you have that "latest BIOS" it may misrepresent the actual size (being limited) but still be functional, although maybe not with DOS/Win9x, e.g. with WinXP after Boot to a within-range partition, will continue to function, ignoring the BIOS (AFAICR).

[rloew]

shae, on 30 August 2012 - 09:21 AM, said:

Am I correct in assuming I can run a 160GB HDD with Win98 and no BIOS support (which detects it as 8GB) as long as just don't use areas >137GB?

It's the BIOS part I'm not sure about. Does it matter for anything other than DOS? Is booting affected? The boot partition is 2GB, so it falls within the 8GB detected by the BIOS.

A DDO is not an option with Windows 9x. It is a necessity.
Any operations by DOS or Windows, before the Driver is loaded, to Drives other than C: can fail. In particular if you do any installations to other Drives that need to be updated on the next boot, they are likely to be done by WININIT in DOS mode.

I have DDOs (BOOTMAN) that can provide the necessary support as well as letting you use the full 160GB.

[Comos]

In the past when I was running Siemens-Nixdorf i486/100 & Win95OSR2 I had similar issue with the BIOS HDD size limitation.Then I disabled the detection on that IDE channel completely and windows during bootup detect the drive (<137GB) and I was able to use it.

[submix8c]

http://dmp.free.fr/t...harg/flopimage/

Look for DLGMAKER.EXE - When run, it will create a WD DLG Diagnostics Disk (Version 2.8). This is the last known WD tool that makes a usable Overlay. I do NOT know if it will work with a HDD that size.

Please note that DDO's are put in the Master Boot Record (1st sector and maybe 2nd, etc?)
and you DARE not use "FDISK /MBR" or ANY other utility that writes to the MBR or the OS will no longer boot.
The DDO can be "uninstalled" with the Floppy as well.

Info/Warning and links from Microsoft (some links inside are no good). More info/a link

HTH and good luck!

This post has been edited by submix8c: 30 August 2012 - 02:46 PM

[shae]

submix8c, thanks for DDO link. I'm not comfortable with the idea of DDOs. Maybe if there were a generic one that could be loaded from AUTOEXEC.BAT or CONFIG.SYS, rather than MBR. But even then it's somewhat worrying.

More specifics on the mobo and HDD: mobo rev 1.10. But the differences are likely in things CPU voltage support, etc., rather than anything pertinent here. HDD-wise, the only extra info there is is the non-documented suffix of the model (stuff like -00JJD0), which I could check if you're interested.

submix8c, on 30 August 2012 - 12:59 PM, said:

Appears that a 32/64GB limit exists (maybe 120gb)?

128GB/137GB is the BIOS limit.

Quote

Have you actually used the External HDD on it? IOW, does it HAVE a "controller" in the enclosure (which BYPASSES the BIOS)?

I used the external HDD. It's not used for booting, and it's on a controller card.

But rloew brought up a good point. Some write actions can be done before Windows booting completes, and those might use BIOS functions. Even if the OS partition fits within the BIOS detected size, I actually do have an additional software partition that doesn't. If only the BIOS treated the HDD as 128GB, or even 10-20GB, that'd be enough, but 8GB is very borderline.

Too bad there's no 128GB clamp jumper on the drive. I might solve the problem by doing more HDD rotations than I anticipated. :-/

Comos, on 30 August 2012 - 01:53 PM, said:

Then I disabled the detection on that IDE channel completely and windows during bootup detect the drive (<137GB) and I was able to use it.

For a boot drive?!

This post has been edited by shae: 30 August 2012 - 04:05 PM

[dencorso]

You want a safe, reliable, generic DDO, RLoew's is the best. It's not free, but it's worth the cost. All "partitioning schemes" used for HDDs beyond the BIOS detection are highly unsafe. These are my 2¢, of course.

[shae]

shae, on 30 August 2012 - 04:01 PM, said:

Too bad there's no 128GB clamp jumper on the drive.

Maybe setting the HPA or DCO max address will be just as good?

[dencorso]

The BIOS IDE HDD Limitations. To follow some of the links therein, you may have to use the Internet Archive's Wayback Machine, due to sites having disappeared into the ether...

[jds]

shae, on 30 August 2012 - 04:01 PM, said:

Too bad there's no 128GB clamp jumper on the drive. I might solve the problem by doing more HDD rotations than I anticipated. :-/

Well, there is a virtual clamp jumper available. Seagate Tools for DOS gives you the ability to set any clamp size you wish. Just temporarily put the drive in a machine that can handle the current/native size, and run the tools from there. Note, this feature is not available in the MS Windows version of the tools.

Joe.

[Foxbat]

shae, on 30 August 2012 - 12:29 PM, said:

The mobo is ASUS P2B, the HDD is a WD AAJB.

submix8c, on 30 August 2012 - 12:59 PM, said:

What SPECIFICALLY is the HDD.

AAJB is Western Digital's current line of Caviar Blue IDE hard drives.

[jaclaz]

jds, on 31 August 2012 - 02:14 AM, said:

Well, there is a virtual clamp jumper available. Seagate Tools for DOS gives you the ability to set any clamp size you wish. Just temporarily put the drive in a machine that can handle the current/native size, and run the tools from there. Note, this feature is not available in the MS Windows version of the tools.

There is a similar thingy for WD drives:
http://wdc.custhelp....,-32-gb,-8.4-gb

jaclaz

[shae]

dencorso, on 30 August 2012 - 08:40 PM, said:

The BIOS IDE HDD Limitations.

Thanks. I'm generally aware of the cause for various limits. But this page is old, so no mention of 137GB. What I do wonder about is whether the 137GB limit is 65536 x 16 x 255 or 65536 x 16 x 256?

Foxbat, on 31 August 2012 - 03:30 AM, said:

AAJB is Western Digital's current line of Caviar Blue IDE hard drives.

The current day AAJBs are probably different than a few years ago (the one I have is from 2006-7), but their "public" model number if the same. The exact details are probably indicated by the suffix (a few letters and numbers, I think 5 of them, e.g.: (WD1600AAJB-?????), but that isn't documented as far as I know.

jaclaz, on 31 August 2012 - 04:29 AM, said:

There is a similar thingy for WD drives:

They just mention various limitations, but I don't think there's a WD tool to set it, but...

jds, on 31 August 2012 - 02:14 AM, said:

Well, there is a virtual clamp jumper available. Seagate Tools for DOS gives you the ability...

That's what I thought about. I don't know if Seagate Tools will work for a WD, but HDAT2 should. I'll try it in a while. Any idea if it's better to limit through setting the HPA or DCO (assuming both will affect BIOS detection)?

EDIT: Well, it seems to work so far, using HPA.

The limit seems not to be 2^28, but 65536 * 16 * 255 (267,386,880 sectors). Anything above, and it's detected as 8GB again (I suppose using CHS instead of LBA?), and strangely also on a 48-bit capable BIOS. Another thing, I used the 28-bit version of SET MAX. The 48-bit seemed not to be detected correctly, but I didn't pay enough attention so it could just be that I set it to more than the 267M limit.

I guess I'll use a slightly smaller number to be on the safe side for 1-off errors (then again, if a 1-off is multiplied... maybe safest would be to set to something common, like the equivalent of 120GB HDDs).

This post has been edited by shae: 31 August 2012 - 07:30 AM

[submix8c]

So glad you FINALLY gave the specific model# of HDD. My brother bought the EXACT SAME ONE in 2008 "open box" sale.

Western Digital Caviar Blue SE. From the Documentation (2079-001026.pdf):

Quote

137 GB Barrier
The previous standard for the IDE/ATA interface uses 28-bit
addressing, which cannot recognize more than 137.4 GB of storage.
To overcome this capacity barrier, hard drives higher than this
capacity have adopted a 48-bit addressing system which can be
supported in newer computer systems with updated controller chips,
BIOS codes, and operating system service packs.
• Windows 98SE and Me require the use of a 48-bit LBA supported
controller card to fully recognize higher capacity hard drives.

You do not have a 48-bit Controller.

Quote

32 GB Barrier
Some BIOSs released before June 1999 stall with drives larger than
32 GB. If you are installing such a hard drive and your system stalls
before floppy or hard drive boot can take place, your system BIOS
may be incompatible with this drive. Follow these instructions only if
your system stalls when adding a drive larger than 32 GB.
Recommended Solution: Obtain a BIOS upgrade from your system
or motherboard manufacturer.
Interim Solution:
1. Jumper the hard drive to your desired configuration per the
instructions in section 2 of this guide.
2. Use the Data Lifeguard Tools software to access full hard drive
capacity. To run Data Lifeguard Tools:
a. Boot from the Data Lifeguard Tools CD.
b. Follow the setup instructions for your hard drive.

Do you think this may imply a DDO? I think so...

Quote

Alternate Jumper Settings
Some older computer systems have difficulty detecting large capacity
hard drives. If your system locks up after the installation of your new
hard drive, try an alternate jumper setting to resolve this issue. For
detailed information on alternate jumper settings, visit our website at
support.wdc.com.

And the Picture is there...

You're going to use HDAT2?

BEFORE JUMPING THE GUN, TRY THE DOCUMENTATION FIRST!!!! I got all of it for my brother. YOU TAKE THE RISK OF HOSING YOUR HDD!!!

MB/MiB/GB/GiB Calculator to help understand. BTW, I have a Compaq EVO here with a BIOS limitation and it does "weird" 240-head instead of the "standard" 255-head so even a 40GB HDD had to be WIPED to start over. I just got a WD1600BB (similar) that "hits the wall" I will test the WD Tools (DDO) on it to see if it will function correctly.

PLEASE NOTE that a DDO does NOT correct the BIOS, it simply "enhances" it and DOES NOT overcome the Win9x 48-bit LBA problem - MUST PATCH THE OS.

This post has been edited by submix8c: 31 August 2012 - 07:27 AM

[jaclaz]

shae, on 31 August 2012 - 05:35 AM, said:

jaclaz, on 31 August 2012 - 04:29 AM, said:

There is a similar thingy for WD drives:

They just mention various limitations, but I don't think there's a WD tool to set it, but...

...but:
http://wdc.custhelp....,-32-gb,-8.4-gb

Quote

If you had setup your drive using the Data Lifeguard Tools 11 option, Set Hard Drive Size and the system BIOS is displaying the size of your drive as ...

jaclaz

[shae]

jaclaz: Oops. I only read the part about 137GB. I wonder if WD's tool is effective for larger capacities, but in a way HDAT2 seems like a nicer tool.

submix: Thanks for all the help. I know it's the 48-bit vs 28-bit issue. I looked for jumper solutions too, but only found mention of a 32GB clamp for WD. I'm not fond of the idea of DDO. MBR dependent, possible translation issues later on, etc.

But for size clamping, setting the HPA with HDAT2 did the trick. There's no risk as far as I can tell. HPA and DCO are tweaked with standard ATA commands, and it's reversible. I just set it multiple times on two computers to see how different values are detected by both BIOSes.

Now, just for the sake of completeness, I'll do some high-LBA tests in plain DOS.

My conclusion so far: for 28-bit BIOSes + Win98, HPA (possibly also DCO) clamping seems like the cleanest option if you don't mind the lost space.

This post has been edited by shae: 31 August 2012 - 07:50 AM

[submix8c]

Hmmm. haven't yet tried it (the WD tools). If HDAT2 works, then fine.

BTW, the CD referred to (in the quote) is the v11 as jaclaz stated. And apparently is not a DDO. Still, I will ALSO try the DDO (to get full size) as well as the CD ("clamp").

edit - don't expect me to "test" very quickly. You could do the same. I gave links to the actual WD DDO and jaclaz (confirmed by me) has given the name/version of the WD Software for "clamping". And (see jaclaz comment below) you're kind of adding to the confusion with such a statement.

This post has been edited by submix8c: 31 August 2012 - 08:18 AM

[jaclaz]

shae, on 31 August 2012 - 07:44 AM, said:

But for size clamping, setting the HPA with HDAT2 did the trick. There's no risk as far as I can tell. HPA and DCO are tweaked with standard ATA commands, and it's reversible. I just set it multiple times on two computers to see how different values are detected by both BIOSes.

What I am clearly missing is, since you have NO issues with BIOS (i.e. the thingy, if I got it rightly, boots normally) what is the issue with simply leaving the "rest of the disk" UNpartitioned? (or possibly using a partition ID that Win 9x surely cannot use/access (like the 0x07 NTFS or one of the 0x8x Linux ones)?

jaclaz