I know of the limits up to 2Gbytes, but understand there are others, especially around 32Gbytes. First, what exactly are those limit values and what causes them? Second, how does one determine the limit of a given motherboard & BIOS? Third, assume a system has a 32Gbyte limit; why would a 40 Gbyte drive give no problems ever, and one of three 120Gbyte drives have minor problems and the others refuse to boot even in DOS 6.22?
On a sunny day (Thu, 21 Dec 2006 09:35:34 GMT) it happened Robert Baer wrote in :
There are 3 issues, BIOS, filesystem, and applications. Some file systems use[d] 32 bits for length of files, this sets the maximum filesize to 2^32 = 4 294 967 296 bytes, say 4GB. This is for example also the max for a .wav file as MS used 32 bits for length in the header.
Some file systems (like ISO DVD) have a bit less it seems, max filesize for an ISO 9660 type DVD is 2GB.
In case of BIOS, there are several ways one can address a harddisk, one is by head, cylinder, and sector, the other, more modern one as Linux does for example, is simply by sector number. This is the way the hardware works anyways, on modern drives the firmware will map the sector number to a good sector, and the sector number is 64 bits IIRC.
The old problems came from translation head, cylinder, and sector (as supllied by the BIOS) to such a sector number, say if each is only 8 bits, then you have
24 bits or a max size of 16777216 sectors, x 512 bytes per sector = 8 388 608 kB or 8MB.There were BIOS fixes for this in the past.
With 64 bit sector numbers we will run into problems too one day......
Maybe you need a BIOS upgrade, maybe you even need an OS upgrade (old Linux Redhat only did 40GB, after that it overwrote the MS Windows FATs on the other partition snif snif, no warnings given), or maybe just buy a modern PC ;-)
have 24 bits or a max size
The file system and OS are not relevant in this case; DOS6.22 (as mentioned) installed in the first and only partition (2Gbytes is max for FAT16) rus well provided one boots from a floppy. Ditto for Win98SE (FAT16 as well as FAT32) and Win2K (NTFS).
will
IIRC.
supllied
have 24 bits or a max size
What is the EIDE buss speed? There are EIDE interface cards with a bios extension to allow you to use larger drives. "Promise Technology" is on brand name. Are you familair with "Belarc Advisor"? It will tell you what motherboard you have, so you can find the MB's specifications. I may have a good 133 MHz card
-- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
hmm i hope not, well maybe in a million years or so, ... in fact with todays technology it would take that long just to write all those sectors. interestingly sectors are still quite small, usualy used in clusters of 4.
Colin =^.^=
have 24 bits or a max size
I did "give up" and have the Promise Ultra 133 TX2 on order; we shall see if that is of help. Thanks for the reference; will look at it.
the limits are somewhat system dependant, the main cause main the bit-width of the registers/variables used to make the computations of which block on the drive to read/write. In other words these are software or firmware limitiations, not limitations of the hardware. replacing the OS and/or adding a card with a BIOS extension can get you past them. if the OS doesn't use the BIOS to identify or access the drive it's possible to boot from other media (floppy, cd, a smaller drive) and then use the larger drive....
either RTFM or suck it and see.
dos 6 is likely going to have trouble with a drive that big.
Bye. Jasen
it's fairly easy to do without special software.
dumping the memory from 960K to 1M will get you a copy of the system bios ans somewhere in there will be the model number of the moard you have,
a coulple of minutes with google will get you a photo of the board and full specs...
eg: on linux. dd if=/dev/mem bs=1024 skip=960 count=64 | strings | less
scan through that for the word "Copyright" or "(C)" and nearby you'll find the model number of the board
-- Bye. Jasen
On a sunny day (Fri, 22 Dec 2006 22:28:01 GMT) it happened "colin" wrote in :
Yes that is true. There are plans for larger sector sizes. But if memory expansion continues the way it has done, say from a 250 kB floppy (Kaypro II) to a 400 GB harddisk = factor 400 000 x 4 = 1 600 000 x, in say 1980 to 2005 = 25 years, in 25 years we should have:
1 600 000 x 400 GB = 1 600 x 4 TB = 6 400 TB, so maybe it will happen sooner then you think: 6.4 TB = 6.4 x 10^152^64 = 1.8 10^19
So around 2050 or so..... But the big comet comes in 2028 or 2029 anyways :-)
IBM just came with a 700GB tape drive. So maybe...
The mainboard ID is usually shown at the bottom of the first screen when booting !
--
Best Regards:
Baron.
It may go by too fast to read if you are short on memory. Just press the "Pause" button to freeze the display.
Regards,
Mike Monett
Antiviral, Antibacterial Silver Solution:
x,
sooner
I gave up with my 4gb dat tape ages ago, when I first got it people were amased I could store several copies of all my disc drives on one tape lol, now it would take a skipfull of tapes just to stotre 1 realy big drive, its also started to work out cheaper to just use another HD than a skipfull of tapes,
700gb is good though, I gues its just about keeping pace.things dont always keep going up at the same rate, just like house prices here, people said they would always be going up, and I should buy sooner than later, fortunatly I sold one house and the one I was buying fell through, then the house prices fell lol.
There must be some molecular limit, I cba to work out how many molecules there are in a std size HD platter these days.
3D storage is already on the cards I hear, although we have only just got into vertical bits now wich was on the cards eons ago.I supose after that limit they will have to move to quantum storage wich would be infinite - apparently.
Colin =^.^=
Belarc Advisor tells you a lot more than the motherboard type. Until you try it you have no idea what all it can do for a computer tech. It installs ands runs in seconds, opens a browser window and displays all the information as a HTML document that can be saved for future reference. It gets fresh data every time its run, so you can compare the current status with an archived version.
That Belarc Advisor does show a lot of info, but fails to show what speeds the IDE can handle. The spec for the VIA P4PB400-FC board states UDMA 66/100/133 oeration modes.
the
1) TFM does not say anything about drive limits in any way. 2) Did i or did i not state this was also tried with Win98SE as well as Win2000?
Do not need to do that; i know what kind of board i have and have a manual as well; none of that info has been useful...
Holographic (3D storage?) is available now, but too expensive for us peons.
It has been useful, in that it showed some programs that i had "uninstalled"; so i got into my search and destroy mode and zapped them. It also showed some programs that i did not know about, and was able to confirm that those belonged to wanted installed programs. But zero info on speeds for the IDE; the motherboard manual became the reference for that.
shit happens.
not in the message I was replying to.
Bye. Jasen
Actually, the limitations are part of the bios and also limitations written into the early to execute code of the OS. MS OS's are famous for not keeping up with hardware for where the bootable code may reside. Often you can find that the beginning of the bootable part of the OS must reside very near the beginning of the disk. Often within the first 32 GB regardless of the partitioning. Even Vista still suffers from this disease.
-- JosephKK Gegen dummheit kampfen die Gotter Selbst, vergebens. --Schiller
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