A3000 Logic Chips: U202, U203, U701, U714

[Castellen]

I've written some additional information on these programmable logic devices here.  I can also supply a set of 4 programmed Lattice devices for US$21 *including* worldwide freight.

[Castellen]

No, only applies to the A3000 & A3000T.  They used the older style PAL devices and are prone to heat problems due to poor air circulation in the case.

[Castellen]

If these devices are the cause of your problems, you're likely to notice video problems after the computer has been running for a short time.  It'll probably be cool when you first power it on, so usually you won't see problems until it's started heating up.

The Atmel and Lattice devices do exactly the same job, you won't notice any difference between them in this application.

Same goes for the speed, even the slowest GAL devices are fast enough for operation in the A3000.  There's no advantage in paying extra for the faster rated parts.

[Castellen]

Sounds like that's your problem then.

There is no advantage with using the faster parts.  Internally they probably use the same die.  During manufacture the maximum speed is tested, ones which perform correctly at higher speeds are sold at a premium price.  Ones which fail at higher speeds are de-rated and tested accordingly then sold at lower prices.

I do have a PayPal account, same as my Email address.  See here for contact details.  Price will be US$22 to cover the PayPal 5%.

Hope that helps.