M55

Processor
Intel® Celeron® D Processor 336

Intel® Celeron® D Processor 341

Intel® Celeron® D Processor 346

Intel® Celeron® D Processor 352

Intel® Celeron® D Processor 356

Intel® Pentium® 4 Processor 524 with HT Technology

Intel® Pentium® 4 Processor 531 with HT Technology

Intel® Pentium ® D Processor 820

Intel® Pentium ® D Processor 915

Intel® Pentium ® D Processor 945

Intel® Core 2 Duo Processor E6300

Intel® Core 2 Duo Processor E6400

Cache
256KB L2 cache - Intel® Celeron® D Processors

512KB L2 cache - Intel® Celeron® D Processors

1MB L2 cache - Intel® Pentium® 4 Processors

2x1MB L2 cache - Intel® Pentium ® D Processors

2x2MB L2 cache - Intel® Pentium ® D Processors

2MB L2 cache - Core 2 Duo processors

Chipsets
Intel Q963

Integrated Intel Graphics Media Accelerator 3000

Q963 "GF" Northbridge

ICH8 Southbridge

SMSC 5407 Super IO

IDE controller
4 Serial ATA connectors

No parallel ATA support

Memory
400MHz DDR2 (Double Data Rate) dual channel memory support

PC2-4200 (400MHz) memory supported

PC2-5300 (400MHz) memory supported

Two 240 pin DDR2 SDRAM UDIMM sockets

Supports a maximum memory up to 4GB

ECC or parity memory is not supported

Audio
Integrated High Definition (HD) PCI AC'97 2.3 compliant codec

ADI1983 HD CODEC

Front - Microphone-in, headphones out

Rear - Line-in, line-out

Jack sensing, jack retasking - software will automatically detect which jack the microphone is using.

Software-based audio (done by processor and ICH8)

Keyboard and mouse
Preferred Pro full-size keyboard

USB Optical Wheel mouse

Networking
Integrated Broadcom Gigabit (10/100/1000)

Bays
One 5.25 inch, half-height 1.6 inch, external access

One 3.5 inch, slim-line 1 inch, external access, diskette drive (select models)

One 3.5 inch, slim-line 1 inch, internal access, hard drive

External ports
Eight USB ( two in front, six in back) [Ver 2.0]

One Ethernet RJ-45

One serial 9-pin 16550 compatible (select models may have a second serial port)

One parallel 25-pin parallel (EPP, ECP), IEEE 1284

Monitor port

Audio line in, headphone out, and microphone in jacks

No PS/2 mouse or keyboard connector

Slots
Slot 1: PCI Express x1

Slot 2: 32-bit PCI 2.3 (5v)

Power management
APM 1.2 and ACPI 2.3

Power supply
225 watt supply with variable fan speed

110 volt or 220 volt operation controlled by a switch on the back of the unit

Security
Security chip

Padlock loop (in rear for optional padlock, Tower only)

Security slot (in rear for attachment of optional cable lock)

No keylock

Power-on password

Configuration password (administrator password)

Hard drive password (user and master)

Boot sequence control

Boot without keyboard, mouse, or diskette

USB/Ethernet/serial/parallel/SATA/EIDE/diskette enable or disable

Disk, removable device, and network device password

Diskette write protect

Front USB port disablement

Cover intrusion switch (select models)

Security chip features:

Offers platform and user authentication (requires download of security software)

Executes all private key-related Public Key Infrastructure (PKI) operations right on the chip (requires third party digital certificate, not included)

Designed to enable secure storage of private keys (requires third party digital certificate)

Supports industry standard cryptographic interface (MSCAPI and PKCS#11)Provides more secure access authentication by coordinating with Windows logons and strengthening Lotus Notes logons

Encrypts and decrypts files, folders, and messages with 1024-bit digital signature and up to 256-bit key exchange

Digital signatures allow non-repudiation and data integrity

Integrates with optional biometrics and proximity badges

Adheres to the Trusted Computing Group specification recognized by over 180 companies

Operating system
Microsoft Windows XP Home Edition

Microsoft Windows XP Professional

Note: Preloaded software utilizes the disk-to-disk recovery method. Select models ship without the Operating system.

Optical drive
48x CD-ROM

16x DVD-ROM

48x32x48x16x CD-RW/DVD combo

Multi-Burner Plus 16x

Hard drive features
7200RPM Serial ATA supported

Intel Graphics Media Accelerator 3000
15-pin VGA output on planar

Uses Intel Dynamic Video Memory Technology (DVMT)

For models without a separate video card, memory supports both system and video. System memory used by video may be up to 32MB if the system has 128MB installed, up to 160MB if the system has 256MB installed, and up to 256MB if the system has 512MB or more system memory installed, depending on video mode.

Source
https://support.lenovo.com/us/en/solutions/pd012466