Frequently Asked Questions

What does the fastest machine in the series mean for a check run?

It ends sooner. The LaserJet Enterprise 600 M603dn clears long payroll and vendor batches at full departmental speed, and this MICR cartridge (CE390X, the magnetic 90X) keeps pace — the rated yield is 24,000 pages regardless of how fast the engine spends them.

If a cartridge fades in the middle of a long check batch, what then?

Pause, swap in the replacement, and reprint the checks printed after the fading began — check numbers and amounts must be exact, so a faded tail to a batch is reprinted, never shipped. A sealed spare beside a high-speed machine is cheap insurance against exactly this moment.

Why magnetic toner at this volume?

Because every check in the batch carries the coded line that bank equipment reads magnetically. At M603DN volumes, a run printed in standard toner is not a small mistake — it is the whole batch returned as exceptions.

Does high volume change the bank-acceptance answer?

No. Acceptance is not guaranteed by the cartridge at any volume; it also depends on your check stock, the printer's condition and the bank's readers. Print test checks on your own stock and confirm with your bank before the first big run, and again when stock changes.

Should the MICR unit stay in the M603DN between batches?

Only if the machine prints nothing but checks. A departmental M603DN normally returns to its standard 90X cartridge for daily work, with the MICR unit stored sealed and labeled for the next run.

What protection backs the cartridge?

A 1-year warranty and 1-year free returns. Support runs Monday through Friday, 9 AM to 5 PM CST.

About This M603DN MICR Cartridge

At $194.41, this MICR cartridge (CE390X / 90X) is the check supply for the fastest printer in its family — a 24,000-page magnetic unit built for batch work on the M603DN. Orders ship from warehouses in IL, PA, GA and CA, and the shipping & returns page details delivery and returns; related supplies are listed under HP.