WANTED: 1mx4 DIPP IC DRAMS why?

I can't seem to find any of the 20pin 1mx4 DIPP DRAMS needed for my futura, try though I might noone seems to have the dumb things, unless I want to buy 500 at $4 a chip. If anyone has the nec. stuff to solder surface mounts to adapter pads or can find these chips it would be appreciated.

I am also looking for RGBI RGB+Sync 15khz analog monitors (not digital like cga).

Thanx
Ryan

Yeah SIPPs are hard to find. I did get some on ePay some time ago. I need 8 1 meg low profile ones myself for a Grid 1520 LT. I did find a few suppliers, like you did, but they wanted to sell at large quantities. Should you find any, let me know, once you've supplied your own needs.

Lawrence

How many of these chips are needed in a bank for 1MB ? Four?

rmay635703 said:

I can't seem to find any of the 20pin 1mx4 DIPP DRAMS needed for my futura, try though I might noone seems to have the dumb things, unless I want to buy 500 at $4 a chip. If anyone has the nec. stuff to solder surface mounts to adapter pads or can find these chips it would be appreciated.

I am also looking for RGBI RGB+Sync 15khz analog monitors (not digital like cga).

Thanx
Ryan

Click to expand...

mikey99 said:

How many of these chips are needed in a bank for 1MB ? Four?

Click to expand...

These are the last generation dipps that were made (by the way a dipp is an individual rams chip), after these they were all surface mount I have a few of these chips but need more to finish off my graphics systems. They were intended for 286 and 386 systems (and printer buffers) and were occasionally used on early 4mb 72pin simm modules and a few 1mb 30pin modules.

Anyway to answer your question, these are 4 bit wide chips 1mbit deep that means the smallest bank on a 286 or in my case Motorolla 68000 is 4 chips per bank (cough 16bits), 4bit x 4 x 1mb = 2megabytes of ram

So in my case I can't bank 1mb of these chips, the smallest would be 2mb per bank, I want the full 2 banks full so I would have 4mb of raster memory.

Too bad I can't find them, a LOT of old devices could use them but most folks were too damn cheap to buy high density chips back in the day and stuck with the cheaper 256kx4 which are totally useless for me as I can't even boot my last OS 7.2

Cheers
Ryan

Micom 2000 said:

Yeah SIPPs are hard to find. I did get some on ePay some time ago. I need 8 1 meg low profile ones myself for a Grid 1520 LT.

Click to expand...

Lawrence,
Don't confine your search to just SIPPs. Those 30 pin SIPPs were just SIMMs with pins soldered on. When needed, I would just solder on small lengths of fuse wire (of suitable width).
I've just been through my memory collection. Whilst I don't have the DIP chips that Ryan is looking for (I just have 256k x 4 bit ), I do have a lot of 30 pin 1M modules.
I do have qty 8 of 1MB 100nS Toshiba SIPs. They are modules where I soldered on fuse wire. They may not suit your needs though due to the speed, and/or their height of 20mm (not incl. pins).
I also have qty 8 of 1MB 70nS Toshiba SIMMs. Height is 15mm (not incl. pins). You or someone else will obviously need to solder on pins (or whatever.)
PM me if you're interested, but note that I can't respond for a few days.

I think I have some of these devices that were used as printer memory upgrades! How many are you looking for again? DaveC

Sorry I just now saw your post. Thanks, but I have a box-full of 1meg simms.
Just too lazy (busy ?) to do the tedius soldering.

Lawrence

modem7 said:

Lawrence,
Don't confine your search to just SIPPs. Those 30 pin SIPPs were just SIMMs with pins soldered on. When needed, I would just solder on small lengths of fuse wire (of suitable width).
I've just been through my memory collection. Whilst I don't have the DIP chips that Ryan is looking for (I just have 256k x 4 bit ), I do have a lot of 30 pin 1M modules.
I do have qty 8 of 1MB 100nS Toshiba SIPs. They are modules where I soldered on fuse wire. They may not suit your needs though due to the speed, and/or their height of 20mm (not incl. pins).
I also have qty 8 of 1MB 70nS Toshiba SIMMs. Height is 15mm (not incl. pins). You or someone else will obviously need to solder on pins (or whatever.)
PM me if you're interested, but note that I can't respond for a few days.

Click to expand...