Power supply problem?

[angelcaio]

Hi
This past week I've been experiencing a lot of stability issues with my Amstrad CPC 464.

I've been experiencing frequent crashes, screen distortion, booting with a black screen, booting with a highlighted border and a gray screen, and it keeps crashing.

I recently replaced the DDI1 clone disk controller with a DDI4 clone without memory expansion.

It's been working for a week.
Before experiencing all these problems, I ran some power consumption tests by connecting the GTS 65 monitor to a smart plug and measured and recorded the consumption data in different scenarios:

There shouldn't be any memory conflicts because Piort sent me the ddi-4 memory expansion disabled after explaining that I had an MX4 with an X-Mem connected and didn't want conflicts between them.

I've tried two different CPC464s and the same GT 65 monitor with the same result.

The controller connected alone does work correctly.

My question is if the consumption can be supported  by the GT 65 power supply or should I buy an alternative power supply to connect the CPC464.

The MX-4 expansion board doesn't have a power connection because I bought it without diodes due to previous problems I had with it.
I mentioned this years ago on this forum, 8and TotO replaced my old MX4 with one without diodes and without a power supply   (https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/issue-with-a-mx4-board/msg168022/#msg168022).
so that it could be powered directly from the CPC expansion port.  This has been going on for years and I haven't had any problems until today.

Any idea?
Do you recommend a PSU?
Or could it be another problem?
Thanks in advance

[angelcaio]

Update.
Today I connected everything except the AMX Mouse, and everything works fine.
The moment I connected the mouse to the system, it crashed in less than a minute.
The mouse is powered by the GT65, and a cable connects to the 5V input of the CPC.
This worked until I replaced the DDI1 Clone with a DDI4 Clone without memory expansion.
I tried powering the mouse with a 5V adapter, but it doesn't work if it doesn't detect any power on the output cable (the one that would connect to the CPC).
Simply measuring the output with a multimeter (it reads 5V or so) makes the AMX mouse work again, until the multimeter cables are removed. I've thought about connecting something that has a 5V power consumption (the red and black cables from a USB mouse to a female barrel connector). Is that a good idea?
Does anyone have another solution? Thanks

[GUNHED]

GT64/65 are 40 years old now, they deliver too few power. Try to use more PSUs for expansions. Never get power directly from the 5 V line of the monitor if you can use an extra PSU.

[pelrun]

The only difference between a monitor "delivering too few power" and one that works fine is a minor adjustment of the VR501 trimpot. It doesn't matter if your new PSU can supply 4A at 5v when the oxidised connectors and connections in the CPC immediately drop half a volt before getting to any ICs. A CPC will be far happier when fed with 5.3V, even if it's only 1A.

[Brocky]

The only difference between a monitor "delivering too few power" and one that works fine is a minor adjustment of the VR501 trimpot. It doesn't matter if your new PSU can supply 4A at 5v when the oxidised connectors and connections in the CPC immediately drop half a volt before getting to any ICs. A CPC will be far happier when fed with 5.3V, even if it's only 1A.

i noticed this too... even with a brand new (recreated) 464 board and brand new power connectors, voltage getting to the chips was always dropping half a volt or more as soon as it hit the board (using external 5v/2A wall wart..a good one!..and no access to an original monitor)... i used a bench power supply set at 1.5A (highest ive seen it pull with 3 expansions on a MX4 expansion board was only 1.2A), and then adjusted the voltage until the z80 read close to 5v on a multimeter... the voltage on the PSU and power jack was up around the 5.6v range...

[angelcaio]

GT64/65 are 40 years old now, they deliver too few power. Try to use more PSUs for expansions. Never get power directly from the 5 V line of the monitor if you can use an extra PSU.

My MX4 Version is "without Diodes" and not has power connection:
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/issue-with-a-mx4-board/msg168022/#msg168022

Can I try powering the AMX Mouse separately with a 5V 2A PSU

And should I power the CPC with a 5V 4A power supply instead of the GT65?

[Brocky]

GT64/65 are 40 years old now, they deliver too few power. Try to use more PSUs for expansions. Never get power directly from the 5 V line of the monitor if you can use an extra PSU.

My MX4 Version is "without Diodes" and not has power connection:
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/issue-with-a-mx4-board/msg168022/#msg168022

Can I try powering the AMX Mouse separately with a 5V 2A PSU

And should I power the CPC with a 5V 4A power supply instead of the GT65?

4A power supply is a bit high... remember if anything shorts its going to pull as much amerage as it can... 4A@5v is 20watts...thats alot of heat to dissipate..and will cause chips to burn up if there is a short...
the cpc464 itself doesnt need much more than about 800mA, so a 2A supply is plenty enough to drive the CPC and expansions...

im not sure what you mean about a MX4 "without diodes".. mine has none... and it can be powered externally by connecting power to the header and changing a jumper on the MX4..

[angelcaio]

GT64/65 are 40 years old now, they deliver too few power. Try to use more PSUs for expansions. Never get power directly from the 5 V line of the monitor if you can use an extra PSU.

My MX4 Version is "without Diodes" and not has power connection:
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/issue-with-a-mx4-board/msg168022/#msg168022

Can I try powering the AMX Mouse separately with a 5V 2A PSU

And should I power the CPC with a 5V 4A power supply instead of the GT65?

4A power supply is a bit high... remember if anything shorts its going to pull as much amerage as it can... 4A@5v is 20watts...thats alot of heat to dissipate..and will cause chips to burn up if there is a short...
the cpc464 itself doesnt need much more than about 800mA, so a 2A supply is plenty enough to drive the CPC and expansions...

im not sure what you mean about a MX4 "without diodes".. mine has none... and it can be powered externally by connecting power to the header and changing a jumper on the MX4..

There is no power socket on my MX4 board, it is powered from the 464 expansion port and I cannot power it any other way.
I can power the AMX mouse separately because it has its own independent power outlet And from this comes a cable to the 464 power supply
This consumption will no longer depend on the 464

[GUNHED]

GT64/65 are 40 years old now, they deliver too few power. Try to use more PSUs for expansions. Never get power directly from the 5 V line of the monitor if you can use an extra PSU.

My MX4 Version is "without Diodes" and not has power connection:
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/issue-with-a-mx4-board/msg168022/#msg168022

Can I try powering the AMX Mouse separately with a 5V 2A PSU

And should I power the CPC with a 5V 4A power supply instead of the GT65?

Extenal power for the Mother X4 can be a good thing, as long as you feed the same power into the CPC. 

[Brocky]

i cant see the mouse and adapter using more than 500mA (probably much much less)... so a 2A power supply should be enough to power both the cpc and the mouse...

[angelcaio]

i cant see the mouse and adapter using more than 500mA (probably much much less)... so a 2A power supply should be enough to power both the cpc and the mouse...

enough power for cpc and mouse But the problem is the consumption of the five cards: X-MEN, XMAS, Mini Booster, Electric Studio light Pen and DDI- Clone 4