Ultrabay

IBM/Lenovo Ultrabay Ultrabay is IBM's, now Lenovo's, name for the swappable drive slot. With IBM's words: "The ThinkPad UltraBay1, also standard with the system, is an intelligent bay that switches its pinout signals to allow the installation of standard and optional features in what would normally be just the FDD bay." Introduced back in the times of the 750 ThinkPads, this technology has gone through redesigns with almost every new generation of ThinkPad models, possibly leading to some confusion that is hopefully cleared up here. The following table gives an overview of the different Ultrabay types, in which models they occurred and what drives are available for them. Note that the optical drive slot in G series ThinkPads is not an Ultrabay: the drives are fixed and not removable.

Over the course of time a number of different form factors have been used for the Ultrabay. These are usually not compatible, but see below for details. Current Thinkpads use either the Serial Ultrabay Slim (accommodates drives up to 9.5mm high) or the Serial Ultrabay Enhanced (accommodates drives up to 12.7mm high). See Ultrabay Devices for a list of all Ultrabay devices.

Compatibility

Overview over Ultrabay types and available devices

Ultrabay Type	featured in	available drives
UltraBay	355, 355C, 355CS, 360, 360C, 360CS, 360P, 360CE, 360CSE, 360PE, 370C, 750, 750C, 750CS, 750P, 755C, 755CE, 755CS, 755CSE, 755CV, 755CX, 760C, 760L, 760E	, 2.88 MB diskette, PCMCIA Cartridge, IBM Wireless Modem ARDIS, IBM Wireless Modem
UltraBay Thick	755CD, 755CDV, 760CD, 760E, 760ED, 760EL, 760ELD, 760LD, 760XD, 760XL, 765D, 765L, SelectaDock I, SelectaDock II	, 2.88 MB diskette, PCMCIA Cartridge, IBM Wireless Modem ARDIS, IBM Wireless Modem
UltraBay II	770, 770E, 770ED, 770X, 770Z, SelectaDock III
UltraBay FX	390, 390E, 390X, i Series 1720, i Series 1721
UltraslimBay	600, 600E, 600X, UltraBase, Portable Drive Bay
Ultrabay 2000	A20m, A20p, A21e, A21m, A21p, A22e, A22m, A22p, A30, T20, T21, T22, T23, Dock, Dock II, X2 UltraBase, Portable Drive Bay 2000
Ultrabay Plus	A30, A30p, A31, A31p, R30, R31, R32, R40, T23, T30, X3 UltraBase	, WorkPad Cradle, Numpad
Ultrabay Slim	T40, T40p, T41, T41p, T42, T42p, T43, T43p, T60, T60p, T61, T61p, Z60t, Z61t, Z61p, X4 UltraBase, X4 Dock, X6 UltraBase, X6 Tablet UltraBase	, Serial/Parallel Port Adapter (T60/T60p)
Ultrabay Enhanced	R50, R50e, R50p, R51, R52, R60, R61, R61i, Z60m, Z61m, Advanced Dock
Serial Ultrabay Slim	T400, T400s, T410, T410i, T410s, T410si, T500, W500, X200 UltraBase, UltraBase Series 3	(Ultrabay Slim battery, see Characteristics), Blu-ray drive
Serial Ultrabay Enhanced	R400, R500, T510, W510, W520, W530, T510i, W700, W700ds, W701, W701ds	(see Characteristics), Blu-ray drive

Compatibility Matrix (read columns as slots with rows as devices that are compatible)

Bay Device	UltraBay	UltraBay Thick	UltraBay II	UltraBay FX	UltraslimBay	Ultrabay 2000	Ultrabay Plus	Ultrabay Slim	Ultrabay Enhanced	Serial Ultrabay Slim	Serial Ultrabay Enhanced
UltraBay	yes	yes	Adapter	-	-	-	-	-	-	-	-
UltraBay Thick	-	yes	Adapter	-	-	-	-	-	-	-	-
UltraBay II	-	-	yes	-	-	-	-	-	-	-	-
UltraBay FX	-	-	-	yes	-	-	-	-	-	-	-
UltraslimBay	-	-	-	-	yes	-	-	-	-	-	-
Ultrabay 2000	-	-	-	-	-	yes	yes	-	-	-	-
Ultrabay Plus	-	-	-	-	-	-	yes	-	-	-	-
Ultrabay Slim	-	-	-	-	-	Adapter	Adapter	yes	yes	-	-
Ultrabay Enhanced	-	-	-	-	-	Adapter	Adapter	-	yes	-	-
Serial Ultrabay Slim	-	-	-	-	-	-	-	-	-	yes	yes
Serial Ultrabay Enhanced	-	-	-	-	-	-	-	-	-	-	yes

Characteristics

UltraBay 

no hot swapping

UltraBay Thick 

thicker version of UltraBay to support CD-ROM drive

UltraBay II 

supports hot swapping; cutout lower right corner of the bezel

UltraBay FX 

combined floppy drive and optical drive found in the 390/390E/390X

UltraslimBay

supports hot swapping; frame, rectangular bezel with beveled lower edge

Ultrabay 2000 

supports hot swapping (except in ThinkPad Dock I); frame, cutout lower right corner of the bezel

Ultrabay Plus 

like the Ultrabay 2000 but can take the Ultrabay Plus Device Carrier which in turn can hold the Ultrabay Plus Cradle for the WorkPad C500 or the Ultrabay Plus Numeric Keypad

Ultrabay Slim 

supports hot swapping; thinner (9.5 mm) than the Ultrabay 2000; cutout lower right corner of bezel; the 4x and 5x series have different battery connector from the 6x series

Ultrabay Enhanced 

supports hot swapping; thicker (12.7 mm) than the Ultrabay Slim but does accept Ultrabay Slim devices

Serial Ultrabay Slim 

supports hot swapping; same dimensions as the Ultrabay Slim; supports Ultrabay Slim battery, but not in models supporting slice battery attached to the bottom of the laptop, e.g. T410/T510 (even then there seems to be some mechanical difficulties—see discussion); some versions with a flat bezel, some versions with beveled lower edge

Serial Ultrabay Enhanced 

supports hot swapping; same width and depth as the Serial Ultrabay Slim, but is 3mm higher; slim devices work fine, but do not fit accurately and (may) disconnect on movement; see the Serial Ultrabay Slim notes about battery

Unofficially compatible

A CDRW/DVD-ROM Superdrive (scavenged from a Mac iBook) will fit in an Ultrabay 2000. The original face won't fit in the bay, leaving a bare metal front. When the drive spins up, it blows a lot of air out. Maybe that's an anti-dust measure?

In general, Ultrabay 2000 CD drives have a standard connector, and can therefore be replaced by most other 12.7 mm drives. You might have to do some cutting of the plastic face plate.

The Ultrabay Slim CD drives however, have a proprietary connector. You can not replace them with any 9.5 mm CD drive.

Linux support

The pinout switching is done by the BIOS and hardware, so that it is completely transparent to the operating system.

• Floppy drives are supported by the standard floppy driver.
• ZIP drive support is possible through the ide-disk driver.
• IDE hard disks and optical drives are supported by the ata_piix or older ide-disk driver in the linux kernel.
• Batteries are automatically handled by the hardware, but can be controlled further by using tp_smapi.
• UltraBay Plus devices should be handled by the USB subsystem, but if the actual devices are is not known.

Hotswapping

See also How to hotswap Ultrabay devices.

External sources

• IBMs page on using a second hard drive adapter in the Ultrabay 2000 slot under Linux

FOOTNOTES [Δ]

1. IBM originally used the spelling "UltraBay" with a capital letter bee but later switched to "Ultrabay" with a lower-case bee.