Lexmark T640: base USB monochrome printing with held jobs review

A local monochrome queue with controlled release

The Lexmark T640 base model is a monochrome laser printer with 350 sheets of supplied input and a documented confidential-print routine. Exact US part 20G0100 suits a directly attached computer queue within the maker's recommended 3,000–14,000 printed pages per month. Its four-line grayscale panel and numeric keypad provide local job controls without turning it into a scanner-equipped MFP.

Check the complete model name before choosing a connection. The base port specification and original part-number catalog distinguish USB and parallel from the network-equipped T640n. Automatic duplex is also an option rather than supplied hardware. An offered used machine may have additions, but those need to be identified individually.

Connect the computer and submit protected jobs

USB Type-B is the straightforward supported computer arrangement for the base package. The front USB Direct interface performs a different job: it accepts suitable stored PDFs for walk-up printing. An internal card slot and a list of compatible network options do not establish that those cards are installed.

The original guide describes local Windows and Mac printing. Install compatible software and choose the correct printer, paper source, size and media type. Verify support on the intended current system; historical driver instructions do not guarantee every later operating system or application.

For confidential output, compatible Windows software uses Print and Hold, while the Mac routine uses Job Routing and Confidential Print. Submit a user name and four-digit PIN using digits 0–9. At the printer, select the user and confidential job, enter the matching PIN and release it. Printed confidential jobs are deleted from memory.

This memory-held routine is separate from optional hard-disk encryption. Ordinary Verify, Reserve and Repeat held jobs also have different behavior and do not all require a PIN. Use the confidential option when local protected release is the actual requirement.

The supplied paper load and optional duplex unit

The 250-sheet drawer and 100-sheet multipurpose feeder total 350 sheets at the stated 20-pound or 75-gsm basis. Letter, Legal and A4 fit both ordinary sources. Adjust the guides, keep below the load line and match panel and software size/type settings. Sources with matching settings can be linked under the documented routine.

Automatic duplex needs the matching 250-sheet duplex unit. That name refers to compatibility with the printer's standard tray, not an extra 250 sheets of input. The unit mounts beneath the printer and changes the space and support arrangement. The base configuration should not be counted as automatic duplex simply because the family manual explains the option.

Suitable envelopes have a separate one-sided MPF routine, with up to ten under the guide's stated conditions. Set Envelope and the actual size. Avoid stamps, windows, clasps, exposed adhesive and damaged stock. The optional 85-envelope feeder is different hardware and is not supplied.

Front PDF printing and larger configurations

For front USB printing, storage must meet the documented USB requirements and use FAT rather than NTFS. The guide excludes encrypted files and files without printing permission. Select the supported PDF at the panel and leave the drive connected until printing finishes; a generic office document is not automatically a directly printable PDF.

The 3,850-sheet maximum input and larger output or finishing arrangements require optional equipment. Base output is 250 sheets. Inspect installed trays and their recognition in the driver, and follow the support-furniture requirements for larger floor-mounted combinations. None of these paper options adds scanning, copying or fax.

Workload, cartridge region and condition

Lexmark declares up to 35 one-sided Letter pages per minute. That is a manufacturer mode, not an application timing result. Its 200,000-page maximum duty rating does not replace the recommended monthly ceiling.

The original US supplied cartridge declares 6,000 pages. Americas replacements include 6,000- and 21,000-page choices under ISO/IEC 19752; do not borrow the T644's 32,000-page option. Specialized label work needs the stated cartridge and fuser-cleaner arrangement. Inspect maintenance condition, electrical label and service clearance on this discontinued model, or choose a documented network or duplex package when those features are essential.