STM 4MB RAM UPGRADE

[microman]

Steve,

How is this for height in the motherboard shielding? Does it need any mods to the shielding?

Any idea when the board might be available?

Thanks

Peter

[Steve]

Do STMs have shielding?? I don't even remember. Sorry my shielding is long gone so can't test that. Keyboard fits fine.

[exxos]

The boards still have not been made up yet so I cannot check.

Considering the STM's had chips on top of chips and bodge wires on top of those I assume the shielding still fitted.. I cannot imagine the RAM board being any taller than that..

[coonsgm]

Hey there folks!

Just installed one of these. I see two photos one with RAM capacitors removed, one with them still in place. I assume it's fine either way?

I'm having the black-white border screen of no boot currently and troubleshooting my way through it...just checking the "instructions" to see if I did an oopsie or if I just damaged my board and need to find what I did.

Thanks!!

[exxos]

Just installed one of these. I see two photos one with RAM capacitors removed, one with them still in place. I assume it's fine either way?

Shouldn't matter. Preference is to leave them in.

Try the diagnostic cart over serial link to PC..

[KaZp3r]

Whats the chances of this working in the 1040 SFF C070523-01 pcb?

[exxos]

Whats the chances of this working in the 1040 SFF C070523-01 pcb?

Interesting thought. Will look into it when I get chance. But I'd assume not, as the chips would have to be in the same order and same spacing.

[GadgetUK164]

Quick question about this upgrade, and a problem I am having!

I've fitted it all OK, works fine in respect to boots from UltraSatan - reports 4MB, can boot diag cart and test all 4MB OK. If I boot from HDD and try and run anything from GEM (eg. Sysinfo) it says there's not enough RAM (It thinks it has 512KB...).

It's running TOS 1.04 too - so I am puzzled how diag cart see 4MB all OK, and some games from HDD work that need more than 512KB - eg. Wings of Death dbug version. I am sure I've seen this before somewhere on a previous ST - is another mod required?

EDIT: Is there something related to the shifter perhaps?

[exxos]

Some original games only checked for 1MB ram. So when you have 4MB the game thinks you have 512k.

Also depending on number of partitions and driver, you could eat up a fair bit of ram there also.

I never known sysinfo complain about ram. You should probably try the simplest basic setup and try again.

[GadgetUK164]

Thanks! It makes no sense, there is an issue here. For example, on my STFM booting same HDD - everything works.
Including the "XTRARAM" test - which sees 4MB on the STFM. On the STM it detects 512KB. Put diag cart in, 4MB seen.... Both machines have 4MB both machines have TOS 1.04.

EDIT: Maybe its related to the original 1MB upgrade that was there before I upgraded now to 4MB?!?
When I removed that upgrade from the shifter area, all I did was remove the wires soldered onto one of the RAM ICs, and the connections made to the MMU from board in shifter area. What other mod is needed on an ST to identify more than 512KB? It feels like something might be missing?

EDIT2: Could it be resistors on RAS and CAS? I re-introduced 2 x 68ohm ones on CAS connections which the original memory used. I also re-introduced the one on the RAS too in order to get RAS connected from MMU to the DIP edge on where the RAM chips would normaly go.