Amiga 3000 zip ram problem

[agr]

Hello,

I'm trying to install zip chips into my recently acquired A3000. The chips are TC514402AZ-70. I've now put 8 of those in U850 to U857 (bank 0). I've put them with pin 1 on the left, next to the capacitors (can read the numbers on the chips from the front of the A3000).

The jumper J852 is put toward the front of the A3000, where it says 1Mx4.

No error on boot, no smoke; the problem is that the new ram is not shown in the WB titlebar or in ShowConfig.
Can someone help me make it working ?

Thanks !

[mechy]

Hello,

I'm trying to install zip chips into my recently acquired A3000. The chips are TC514402AZ-70. I've now put 8 of those in U850 to U857 (bank 0). I've put them with pin 1 on the left, next to the capacitors (can read the numbers on the chips from the front of the A3000).

The jumper J852 is put toward the front of the A3000, where it says 1Mx4.

No error on boot, no smoke; the problem is that the new ram is not shown in the WB titlebar or in ShowConfig.
Can someone help me make it working ?

Thanks !

Those are static column rams.Should work assuming they are good ram,but i have run into oddities with some A3000's and toshiba ram before.What ramsey/Dmac revisions do you have? is this machine 030 or any accelerators installed?3.1 roms?

[agr]

It's a standard 030, KS31, board rev 9, no accelerator.
Ramsey is 390541-04
DMAC is 390537-02

[agr]

It's a standard 030, KS31, board rev 9, no accelerator.
Ramsey is 390541-04
DMAC is 390537-02

EDIT: sorry for the double post but I having problems with chromium browser on this board and in amibay (also edit button does not work on chromium)

[Selles]

Amiga 3000 memory is installed in "banks" or groups of 8 chips per bank.  For instance, if you installed just 4 megs (8 chips) the first zip would go into the first socked, then you would skip 3 sockets and plug in the next zip, then you would skip 3 more sockets and plug in the next zip, and so on.  The zip ram is not plugged into the zip sockets in a row, like the DRAMs are.

[tone007]

I've mixed static and FP RAM, if that's what you're doing, make sure FP is in the first socket of the first bank.

[agr]

All the chips are the same: SC.
I have the same problem with the 32 chips fitted. After system boot, 0 other ram

EDIT: chips are 70ns

[strim]

All the chips are the same: SC.
I have the same problem with the 32 chips fitted. After system boot, 0 other ram

EDIT: chips are 70ns

Dude, I've been there. If you have money, then don't waste your time and invest in ZorRAM (or ZIP to SIMM adapter if you will stumble upon one). Of course ZorRAM is a bit slower than on-board RAM, but it will save you a lot of headaches related to ZIP RAM chips...

My A3000 came with 4MB of Fast. I've tried to install more by adding ZIPs. Theoretically chips I've acquired were compatible with those installed in my A3000 - same type, same speed, installed in correct banks, etc. But it would never not work. In my opinion A3000 onboard RAM is extremely difficult do expand. Some people did this and had no trouble at all, but I've wasted many hours and got nothing! Finally I gave up and bought ZorRAM, which is an excellent RAM expansion.

[Zac67]

Are the ROMs A3000 type? (Is SCSI working?)
On my 3k several pins of the ZIP sockets had no solder, you might want to inspect them. Have you tried different ZIPs in the first bank? If there's a defect chip, none will be detected.

[agr]

Yes, the ROMs have a sticker saying A3000 on them, branded Escom !? Don'know if they are the right one but the A3000 works fine and boot from the 512MB SCSI HDD. I did not inspected the soldering of the ZIP sockets as it require to completely remove the motherboard. I have also tried a set of 256k chips without success.
I also tried an A2058 Z2 memory board and it works fine.
Do you know any way to diagnose Ramsey ?

There is one strange modification on this motherboard, a 42MHz oscillator add-on wired next to the FPU. Any info on that is welcome ?

[agr]

I've found something intersting: I moved 1MB of chip ram to the fast ram DIP sockets and it works !
So, I will check the connections between the DIPs and ZIPs banks 0, it can be the soldering issue...

[adz]

Forget messing with ZIP chips, contact DJBase on this site and inquire about his ZIP to SIMM converter for the A3000

[tone007]

Any damage to the motherboard in the battery area?

[agr]

The battery is starting to leak... but no damage yet.

@adz
If the zip chips are not working, I give little chance for a ZIP to SIMM converter to work on top of those zip sockets...

[Zac67]

I've found something intersting: I moved 1MB of chip ram to the fast ram DIP sockets and it works !

With or without moving the RAM size jumpers (J852/853)?

If DIP 256kx4 work and ZIP don't it's clearly a problem with the sockets.