So, since the HP Vectra turned out to be such a bust (what a waste of money... gold scrap now!), I'm going to do what I probably should have done in the first place. I'm an electrical engineer, PCBWay exists, and cache chips are a thing I can buy. So I need to find someone who has the 128kb cache module out of a Compaq Deskpro 4100 or Prolinea 4100 who is willing to peel the stickers and send me the highest resolution pictures they can so that I can try to reproduce it.

It's a long shot because it is most likely a multi-layer PCB -- but hopefully it is just front & back with an internal ground and power plane and easy enough to figure out. If there are hidden traces I would need a cache module in hand and since near as I can tell -- they don't actually exist -- that is probably a tall order.

I've seen a picture of the 128kb cache module -- but it was pretty low resolution and had stickers obscuring traces. So I know at least one exists. I also know Lazibayer had one at one point but he/she hasn't been online in over a year and also said that they bought it for another PC. Since it didn't work for him/her it has probably moved on to a new home or to the landfill. There is also a 256k module but that one looks much harder to duplicate. Quad packaged cache chips with lots of traces underneath. More likely to have luck with the 128kb cache using DIPs.

- AN