Name: Skid Date: July 14, 2004 at 06:22:00 Pacific Subject: Win ME 137Gb limit - warning OS: Win ME CPU/Ram: XP2600 512Mb
Comment:
Beware! Win Me appears to handle greater than 137Gb BUT as soon as you access over the 137Gb limit Win ME wraps the address and you write out somewhere in the the first 137GB
Just spent 4 days recovering data because of this.... it can wipe out boot records too, which misleads you into thinking it is a virus.
Remember, Win me - 137Gb is the drive limit - regardless of how you partition. It won't warn you.
skid, have you seen any documentation on that problem? Does anyone else know anything about this? I am having no such problems with my 250Gb USB hard drive using Windows ME. I would like to know if there may be problems in the future for this drive.
I think the problem affects the IDE driver, may be why you dont see a problem with USB drives. To test it out, I had a 200Gb drive with 3 partitions c:(8G) d:(8G) e: (176G. )I "washed" e:drive (using Ztree)i.e. to zero it out - when it reached 120G - bang - the MBR was wiped. Tried two m/c different MB/hardware.(Both Via chipset though- 2004 vintage) Also used Voptme instead of Ztree - same result.
Most people will not notice until their drive fills up and even then it may wipe sectors in some files you don't know or check.
I am 99% sure that there is a problem with Win Me.
I found the info below on Western Digital Web site.
137 GB Hard Drive Capacity Barrier Implementation of 48-bit Addressing Required for Hard Drives Larger than 137.4 GB The need to break the 137 GB hard drive barrier is spurred by today's advanced applications, including digital video (DV) and music recording/editing programs, personal video recorders (PVRs), set-top boxes, network attached storage (NAS), and RAID solutions. All of these applications can use up over 100 GB of storage space quickly. The Advent of 48-bit Addressing Western Digital is the first company to ship a 200 GB drive using 48-bit addressing to break the 137 GB barrier. 48-bit addressing is the newest ATA storage interface standard to emerge from the organization dedicated to setting hard drives standards, the American National Standards Institute’s (ANSI) T13 Technical Committee. Most ATA interfaces in use today employ a 28-bit addressing sytem for data transfer between the operating system, BIOS, and hard drive. The major differences between 48-bit addressing and 28-bit addressing are as follows: · In 28-bit addressing, there are only 28 bits available to access a given address on the hard drive, which when all bits are set equates to 137 GB. · By doubling the number of bits that can be used to access a given address, 48-bit LBA addressing pushes the maximum storage limit to 144 petabytes. An additional benefit to the 48-bit capabilility is the ability to transfer more than 256 sectors per command (i.e., up to 65,536 sectors per command). Interoperability between 48-bit and 28-bit addressing maintains compatibility between older hard drives and new, larger hard drives installed in the same system. Hardware and Software Solutions Employing the new technology required to break the 137 GB barrier required the efforts of hard drive manufacturers, operating system (OS) vendors, and BIOS companies. Hardware and/or software solutions were required from each to enable implementation of the 48-bit address feature set. Business Entities Solution Hard drive manufacturers Change in the system ASIC and/or development of new interface chips on drives or PCI add-in cards that allow deployment of 48-bit addressing. OS vendors The increase of storage device addressing from 28 or 32 bits up to 48 bits or more. BIOS companies Reworking of software to recognize increased device capacity and enable the passing of 48-bit commands to the devices.
Industry Acceptance and Compatibility The new 48-bit addressing standard has quickly become accepted by the industry, with support from Microsoft, Intel, Via, and every hard drive manufacturer. The current plans for Serial ATA, the next generation ATA storage interface, call for the transparent utilization of the 48-bit addressing standard as part of the protocol. In the future, most new systems will be equipped to natively handle large drives. Please check with your system manufacturer if you require an adapter card or if they offer online support for your current equipment. Summary The ever-growing demand for storage space by today's storage-intensive applications has prompted development of 48-bit sector addressing to break the 137 GB barrier for hard drives. The ANSI T13 Technical Committee developed 48-bit addressing, which is interoperable with the previous 28-bit addressing standard. The final industry-wide implementation of 48-bit addressing is underway, and the standard will also be utilized in the development of Serial ATA, the next generation ATA storage interface.
"Maxtor Installation Guide Win98/ME/2K/XP" You must have Ultra ATA/133 PCI drive controller for drives larger than 137 GB. (ie; 48 bit LBA controller and drive). ATA/100,ATA/66 and ATA/33 do not support drives larger than 137 GB. Win 98/ME Scandisk and Defrag do not operate properly on partitions larger than 137 GB.
WinXP Sp1 and higher do not have these requirements/limitations.
Well I *definitely* have a bios that supports 48 bit LBA, the driver is the latest Via 4 in 1 Hyperion Driver which I *presume* supports 48 bit LBA.
WinME (with all the patches) definitely goes tits up when writing beyond 137Gb (though only when it overwrites MBR or critical system files) and not just when using Scandisk and Defrag. And it does it by writing across partitions - i.e. it is a Drive limitation.
The 137 GB limit The old ATA protocol uses 16+4+8 = 28 bits to specify the sector number, and hence cannot address more than 2^28 (or 268,435,456) sectors of 512 bytes. This puts the ATA interface maximum at 137 GB.
FAT32 is NOT the problem. It is the ATA protocol that is the problem.
Windows 98SE and WinME has a default limitation of 137 GB supporting ATA interface disc drives. Therefore, your hard drive partition will have a maximum size of 137 GB even if the Hard drive is larger than that.
To use greater than 137 GB you need 48 Bit LBA mode working. This needs to be supported by the Hardware, BIOS and the OS.
Only WinXP SP1 and Win2k SP3 or above support 48 bit LBA mode.
Certain add on IDE controllers (e.g. Promise Ultra100TX2) also support 48 Bit LBA mode.
Intel Application Accelerator (therefore only certin intel chipset motherboards) have a special driver which supports this mode.
For example the Intel Application Accelerator supports the following chipsets: 810, 810E, 810E2, 810L, 815, 815EP, 815G, 815EG, 815P, 820, 820E, 840, 845, 845E, 845G, 845GE, 845GL, 845GV, 845PE, 850, 850E, 860.
I do not believe that the VIA chipset supports it (I could be wrong on this).
Significant Hard drive issues kick in at 127 GB and the problem worsens at 137 GB. My Website (Homepage link) under the section titled "Working with Large sized Hard Drives, especially 127 GB or bigger" deals quite extensively with this in more detail.
The problem is, initially, it may seem to all work perfectly until you exceed 137 GB and then bang you are faced with big recovery problems.
___________________________________________ ☺ When everything else fails, read the instructions.
The problem is due to poorly written code in the IDE port driver. Instead of processing requests for high numbered sectors, or at least returning an error, the driver falls through to old code. I have written a patch for Windows 98/98SE/ME that resolves this problem. It is available on my website at http://members.aol.com/rloew1.
