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Rottendog Amusements products are back in stock!

Rottendog MPU327-4 MPU / Driver Combo Williams System 3, 4, 6

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Rottendog MPU327-4 MPU / Driver Combo Williams System 3, 4, 6

Availability: In stock

Product Details


The issue with Black Knight and others has NOT been resolved. Rottendog has removed all System 7 games from the compatibility list until further notice.

The MPU327 is NOT compatible with Hyperball      Original MPU and Drivers for Hyperball are available on our website here.

A new MPU and Driver are available from Swemmer Electronics for all System 7 games including Black Knight.

If your MPU and driver board sustained damage from either battery acid leakage or bad repair, this new Rottendog replacement combination board is the answer. One board that replaces both the MPU and driver. We've tested this board in our own games and are very pleased with the performance. Replaces the MPU and Driver for System 3, 4, and 6 games. Rottendog part # MPU327-4.

Update: The MPU327-4 revision has improved the switch matrix, making it more robust and less easily damaged by old diodes on the playfield.

Advantages: - Eliminates the extremely problematic 40 pin connector that interconnects the original boards together.

- Eliminates the need to swap out game ROMs. Game ROMs are select-able via DIP switch.

- Comprehensive on-board diagnostics.

- Uses 6802 instead of 6800 microprocessor.

- Single commercially available oscillator component for timing.

- Williams WPC style controlled lamp circuit design (TIP107).

- Logic level FET drivers for all solenoids and lamp controls.

- Single shot (70ms) for special solenoids (no more burned board due to shorted contacts)..

- Uses sockets for common failure components (micro, PIA and RAM).

- Low voltage reset preventing microprocessor lock up.

Upgrades: NVRAM -NO BATTERIES EVER! Battery and SRAM will be removed and NVRAM installed.

K's Arcade recommends to have all your new pinball circuit boards installed by a professional technician.

Tech Note: Never work on a game, adjust switches, change bulbs, etc while the power is on.

Tech Note for Flash Version 1486-1: Flash Adjustments (PDF) Contact Us

SKU: 882-RTD-MPU327-S3B45

Game Compatibility

Additional Information

Condition New: Item is a new replacement part and comes with a manufacturers warranty. Please contact us prior to shipping your item under warranty.
Used By Game Algar, Alien Poker, Blackout, Contact, Disco Fever, Firepower, Flash, Gorgar, Hot Tip, Laser Ball, Lucky Seven, Phoenix, Pokerino, Scorpion, Stellar Wars, Time Warp, Tri Zone, Triple Strike (Shuffle), World Cup

All parts purchased through this site are under warranty. For specific warranty information please see the product categories below. K’s Arcade recommends that all boards and electronic parts be installed by a professional. The installation of these parts can cause damage to your game or part if installed incorrectly or there is an underlying problem that has not been addressed.


Please note: The installation of any part in your game may not fix the problem. It does not mean the part is defective. Often there is either a known or undetermined problem that is not alleviated by the installation of a new or refurbished part.


If you believe that your part has malfunctioned and is in the warranty coverage period, please contact us before sending it in for authorization via email. We will help to determine the next best steps for your particular part. We always try to work with a customer first before recommending that they send in their board for testing/warranty. It is best to contact us via email. Please be sure to provide the following information: Your name, the type of board, the game name (i.e. Black Knight), and what the game is or isn't doing. A technician will reply promptly to your email.


IMPORTANT WARRANTY INFORMATION: There will be a $35 testing charge for boards that are sent back to us under warranty and are tested with "no problems found". Because all boards that leave our facility have been game tested, those that come back and that have legitimate warranty issues is less than 1%. In most cases, there are other undiagnosed problems with customers' games which may cause the appearance of a malfunctioned board. Most boards that come back to us have no problems whatsoever. The testing fee has been implemented to recover the time it takes to test the board. There is NO testing fee if we find problems. We fix the board and send it back at no cost to the customer.

NOTE: Parts that are returned to us damaged due to power surges or other external sources are not covered under warranty. If we are able, we can repair the damage at a reasonable cost at the customer’s expense.


New boards purchased through K’s Arcade come with the manufacturer’s warranty as described on the boards detail page on this site. If for any reason the board malfunctions please contact us immediately and we will direct you accordingly.


All refurbished and new old stock boards are game tested and come with a 30-day warranty.

Return Policy

All parts returned must be in their original sealed packaging to qualify for a refund. Parts must be returned within 7 days of receipt and must be accompanied by an RMA# from K's Arcade. There is a 15% restocking fee for all returned items. Open or damaged items do not qualify for a return. Please contact us if you are not sure if your item can be returned.

General Shipping Details

During checkout customers can choose to ship via regular Priority Mail service or UPS. The only guaranteed service is UPS second day or UPS next day air which is available to most locations, there are some exceptions. Regular domestic Priority Mail shipping can typically take 2 - 3 days once the package is in the mail stream but could take longer during peak delivery times like February and December. Customers who need their order shipped quickly are encouraged to ship using UPS second day or next day air. Once a order has left our facility and is in the hands of the postal system we have little control over how long it takes to reach its destination. 

K's Arcade offers Priority Mail International shipping for customers located outside of the US. International shipments can take up to a month from the date of shipping to arrive. Delays often occur once a package is in the customs facility of the receiving country. International customers may be responsible for paying VAT or duty on their packages which is to the responsibility of the customer. K's Arcade reserves the right to charge a small handling fee for international orders.

Special Shipping Details

Standard or typical shipment:

Parts will likely ship within one to two business days. All orders over $100 will be shipped with insurance to cover loss or damage and may require a signature. Below is information regarding the shipping of non-standard items.


Due to the unique nature how we package transformers, they may take up to two or more business days to ship. In many cases transformers and transformer assemblies can be shipped within the United States using a Priority Mail Medium Flat Rate box. If that is the case then K’s Arcade will refund the difference in shipping to the customer. The website calculates the shipping for a transformer as though it ships in a standard Priority Mail box to accommodate all shipping scenarios.

If other items are purchased along with the transformer the other items will likely ship in another package to prevent damage. If multiple packages are require to fill an order, the customer may be charged for additional shipping if necessary. This is our policy for both domestic and international customers. 

Boards with ROMs (CPUs/MPUs and sound or display boards):

In many cases these items require ROMs to be programmed and installed prior to shipping, therefore it may take up to two or more business days to ship.

Boards with Lithium batteries:

These items require a Lithium wafer battery which K’s Arcade provides and installs prior to shipment in order to be in compliance with Federal shipping regulations.

For international shipments: Some countries prohibit the shipment of any Lithium batteries. In this case, no Lithium battery will accompany the board and the customer must provide their own battery.

Back glasses:

K’s Arcade uses UPS to package and ship back glasses due to the fragile nature of these items. We coordinate the drop off of the glass at a local UPS store who then packages and ships the glass with guidance by the customer. Customers can choose which level of shipping they desire and pay for the shipping directly with UPS. We have successfully shipped back glasses this way all over the world with a 100% success rate. Back glasses can also be picked up by the customer and must coordinate with K’s Arcade to do so.

Pinball games:

New Stern games can either be picked up at our location or drop shipped to the customer. Shipping is additional and dependent on your location. Please contact us so that we can give you a shipping quote. Shipping is through a freight company who we have used for years with great success. In most cases we do not stock new games so there will be some lead time for order processing and shipping.

 Pre-owned games can also ship, via freight, from our location to yours – again, at a cost to the customer.