Adding some memory to A4000D (rev B) mobo

[macce2]

Hello,


Maybe a kind of noobie type question, but I'd like to replace
my current 80 ns simms with 60 ns ones.
Would this propably work; or is any kind of additional modification
needed ..?!
I have jumpered the Rom speed as 160 ns. (?!)

Is it true that the memory simms to be used on A4000 mobo

should be of FPM type; or would EDO

type also work..?!
Would a 4 mb simm work on the Chip memory slot ?
Or does it have to be a 2 mb simm (if you want full 2 mb chip!) ..?
Any additional advice appreciated.

[cpiac64]

the 4 mb simm on chip memory slot work like a 1 mb

8 mb simm work fine on chip memory slot

[hese]

4MB SIMM works just fine as a 2MB SIMM when you set the jumpers correctly.
Set both J213 and J214 to 8MB and you get 2MB Chip RAM.

[grelbfarlk]

Originally Posted by macce2

Maybe a kind of noobie type question, but I'd like to replace
my current 80 ns simms with 60 ns ones.
Would this propably work; or is any kind of additional modification
needed ..?!
I have jumpered the Rom speed as 160 ns. (?!)

Is it true that the memory simms to be used on A4000 mobo

should be of FPM type; or would EDO

type also work..?!

Rom speed doesn't have any effect on RAM usually, that's for setting the speed of your Kickstart ROMs. Like maybe if you burnt some EPROMS a few too many times the slower setting might work.

Try running SpeedRamsey after you have switched to 60ns RAM. Otherwise it won't be any faster. In some cases I was able to run SpeedRamsey stably or other times I could overclock the A3640, but it was a crapshoot either way. SpeedRamsey usually was more reliable.

I was not able to get either to work reliably with the 64MB mod, but I think some people might have gotten that working reliably?

EDO has worked fine for me in an A4000 motherboard, about as often as random FPM RAM does, so in my experience there isn't any real difference.

[macce2]

With original simm slots and connecting clips;
Are low-profile one simms necessarily needed (?!);
or would normal profile ones propably fit also..?

[Jope]

Normal ones fit well, but ones with a thicker circuit board will not lock that well into place with the original plastic simm slots.

[macce2]

Originally Posted by hese

4MB SIMM works just fine as a 2MB SIMM when you set the jumpers correctly.
Set both J213 and J214 to 8MB and you get 2MB Chip RAM.

Is that supposed to safely work on a A4000D revision B motherboard..?!
Is there any degree of risk of damaging the hardware (mobo, Alice chip)
with the jumpers J213 & J214 set to "wrong" state ..?

[jbenam]

Originally Posted by macce2

Is that supposed to safely work on a A4000D revision B motherboard..?!
Is there any degree of risk of damaging the hardware (mobo, Alice chip)
with the jumpers J213 & J214 set to "wrong" state ..?

Not really, from my experience. It will just detect the wrong amount of RAM.

[macce2]

Just got the new 4 mb simms installed. Those are Hyundai fpm 60 ns simms.
I decided to leave my old Chip ram simm ( not sure, maybe 80 ns ?) installed
and only changed the 4 Fast ram simms.
Physically, my new simms seem to fit quite well.
When I had re-installed all my Zorro cards back in place,
I first got red screen on bootmenu(!).
Naturally, I was shocked; but after re-seating my BigRamPlus card on
the third slot everything was ok again ( my red screens have been rare!).
I quick tested my memory with AmigaTestKit; ok.
I run Ramseyconfig in my startup-sequence with the arguments "Burst; Wrap " etc.
When running Scout, it still states my motherboard Ram to be 80 ns.
I began to think, whether it's because of my Chip ram simm with 80 ns...?!
Or is the 256 mb of ram on BigRamPlus somehow "slowing down"
the (detected by Scout) memory access time ?
I also have Fastlane card installed, with 16 mb 60 ns Ram.
How to test my new simms that they could actually work 60 ns ..?!
Btw; I thought that SpeedRamsey was A3000 only..?

[hooverphonique]

There's no way to read through software what speed your simms are, as the presence detect pins aren't used. The only way to know if your simms work with ramsey skip mode is testing the stability of the system.

The supported ramsey setup is different depending on which cpu you have, afaik.
For instance, burst is not supported when using a3640.

[alexh]

Originally Posted by macce2

Btw; I thought that SpeedRamsey was A3000 only..?

No. A3000 & A4000 both use a Ramsey chip

[hese]

Originally Posted by macce2

Is that supposed to safely work on a A4000D revision B motherboard..?!
Is there any degree of risk of damaging the hardware (mobo, Alice chip)
with the jumpers J213 & J214 set to "wrong" state ..?

Of course it safely works on A4000D, I would not have mentioned this otherwise.

I have used this setup for over ten years and works just fine.

[macce2]

Thank You; so I decided to replace the chip ram simm with a 4 mb 60 ns one, too.
I changed the jumperings J213 and J214.
That does seem to work ok; so far.
RamseyConfig works, Speed Ramsey does not. (!?)
To be more precise; how do you exactly "enable skip mode of Ramsey" ..?
Which options should I give to RamseyConfig (or SpeedRamsey or SetRamsey..?!?) !?
After running RamseyConfig on startup-sequence (with options: BURST; WRAP; Delay 380 ?) I think I get about 0,01 Mips increase (27,90) on speed test with SysInfo;
and -occasionally- some moderate increases on hd access speeds (Fastlane Scsi) (that's quite interesting).
But when running Scout; it still states the mobo Ram to be 80 ns.

[hooverphonique]

Originally Posted by macce2

After running RamseyConfig on startup-sequence (with options: BURST; WRAP; Delay 380 ?) I think I get about 0,01 Mips increase (27,90) on speed test with SysInfo;

I think SysInfo's speed test runs out of the cache, so try disabling them to include memory speed - otherwise use a proper memory benchmark, e.g. bustest or AIBB.

[SpeedGeek]

Originally Posted by macce2

Thank You; so I decided to replace the chip ram simm with a 4 mb 60 ns one, too.
I changed the jumperings J213 and J214.
That does seem to work ok; so far.
RamseyConfig works, Speed Ramsey does not. (!?)
To be more precise; how do you exactly "enable skip mode of Ramsey" ..?
Which options should I give to RamseyConfig (or SpeedRamsey or SetRamsey..?!?) !?
After running RamseyConfig on startup-sequence (with options: BURST; WRAP; Delay 380 ?) I think I get about 0,01 Mips increase (27,90) on speed test with SysInfo;
and -occasionally- some moderate increases on hd access speeds (Fastlane Scsi) (that's quite interesting).
But when running Scout; it still states the mobo Ram to be 80 ns.

You can't use BURST or PAGE mode on an A4000 because the PS2 72 pin SIMMs are always FPM RAM. You can enable BURST mode as long as the CPU/accelerator card doesn't support BURST. WRAP mode is an option which only functions in BURST mode.

The only RamseyConfig option you can use is PAGE mode and REFRESH mode. You have already determined that SpeedRamsey doesn't work reliably... and that's exactly why RamseyConfig doesn't support it.

[macce2]

I'd would like to get more information; regarding Amiga Ramsey chip control and the memory modes etc. generally;
RamseyConfig app etc. ..?
Some more technical info would also be nice, even if i'm no programmer per se.

[macce2]

It seems that the PAGE mode of RamseyConfig doesn't work on my system.
What could be the reason ?!
What exactly does the REFRESH mode do..?!
What are the (theoretical) advantages of it ?!
The smaller the value, the better..?!

[SpeedGeek]

Originally Posted by macce2

It seems that the PAGE mode of RamseyConfig doesn't work on my system.
What could be the reason ?!
What exactly does the REFRESH mode do..?!
What are the (theoretical) advantages of it ?!
The smaller the value, the better..?!

What result did you obtain (or not obtain) which makes you think PAGE mode doesn't work? If you enabled PAGE mode then RamseyConfig should report Page mode = 1. Please be more specific about your results.

REFRESH mode is the number of clocks counted by the Ramsey refresh counter before performing a DRAM refresh cycle. In theory, the refresh time period for PAGE mode is shorter than NOPAGE mode but no one has reported any problems about this yet.

[macce2]

When I run RamseyConfig with the PAGE option, my system
freezes immediately.
I would like to know a little more about the REFRESH mode options !?

[SpeedGeek]

Originally Posted by macce2

When I run RamseyConfig with the PAGE option, my system
freezes immediately.
I would like to know a little more about the REFRESH mode options !?

I suppose PAGE mode could fail with EDO RAM installed, but this type of RAM is not very common in the 4MB size SIMMs. I would suggest you check the type of RAM you are using.

There not much more to be explained for REFRESH mode than what was already explained. The time period (per clock) is determined by Ramsey clock speed and the REFRESH time period is determined by the number of clocks counted.