Unable to see external seagate drive 3terabyte

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Hi my seagate external drive 3T - I am unable to see files on it bu on the BIOS I see it is available? Any idea's running on vista
 

compulsivebuilder

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Jun 10, 2011
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Have you used the drive at all? If not, then it has to be partitioned and formatted.

A 3TB drive requires special handling - it must be formatted as a GPT drive to be used under Windows, and it can only be used as a data drive unless you are using a UEFI motherboard and a 64bit OS (I think).
 
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I have investigated it further and found the diode was blown on the boards (12V protction) and I have removed it to find the drive now works. happy days. mike
 

MrBig55

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Jun 27, 2011
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you removed a diode ?? My god I hope you didn't screw your board there... best would be to RMA the faulty hardware to the manufacturer. They will send you a new and hopefully working one.

@CompulsiveBuilder

Yes you need a 64bit Windows 7 for it to be able to access the drive, but it's no longer needed to have a UEFI Bios if the motherboard manufacturer is using some trick. Let me explain:

Gigabyte Z68XP-UD3 motherboard is using a regular BIOS but still it can access AND allow installation of windows on those ultra big drives because they used a trick in their BIOS to do so. Some other manufacturer might have done the same for some board out there. Oh well that was not the subject but it's fun to know :)
 
@MrBig55, the diode in the OP's case was a 12V TVS (transient voltage suppression) diode. It protects the drive from overvoltages on the +12V input. There is a similar 5V TVS diode on the +5V input. It is quite OK to run a drive without the diode ... provide that you never make a mistake with the supply voltage, eg using a 19V laptop adapter instead of the supplied 12V adapter. Otherwise you can replace it with an SMBJ12A from Farnell, Mouser, Digikey.

As for the file system, it is quite OK to use an MBR file system on a >2TB drive, even in Windows XP, provided that the LBA size is adjusted to keep the total numbers of LBAs within the 32-bit limit. In the case of Seagate's FreeAgent GoFlex 3TB drive, even though the HDD reports that is has 512-byte LBAs, the bridge board inside the enclosure actually reports an LBA size of 4KB to the USB host.

See these threads:
http://forums.seagate.com/t5/GoFlex-GoFlex-Desk-GoFlex-Pro/my-tv-does-not-show-content-from-GoFlex-Desk-3tb/m-p/109000

http://groups.google.com/group/comp.sys.ibm.pc.hardware.storage/browse_thread/thread/a776439e9713f3f2/7a4d674ed5080cc6#7a4d674ed5080cc6