More trouble w/ 4000T.. PSU maybe? Help....

[marcfrick2112]

Hey,

Could anyone give some advice regarding a recommended replacement PSU for a 4000T (with lots of stuff in it) Also, what symptoms would an under-powered Amiga show??
  I found a 300W AT PSU locally, I wanted to make it as painless as possible, but maybe the extra 50W isn't enough?
I had my system working fine for several hours with this PSU, I formatted a 9GB HDD, copied some files, etc. Then, next time I booted I got just a black screen, I re-boot, and I get a 'software failure 8000 0004' on a blank WB screen. This was exactly what happened before the orig. PSU died...
Anyone have any ideas? I can get to the Early Startup, but (still) can't boot 3.9...OK, I know it's a working 3.9 + BB1+2 install. If I have to find an ATX PSU with higher wattage, what about the power switch? The AT (4000T) PSU has an 'on-off' switch, while ATX PSU's have a momentary action switch, correct?

Grateful for any help....

[rkauer]

http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/body_amiga_power_supplies.html#Fitting_a_new_PSU_to_an_A4000

[marcfrick2112]

Thanks rkauer:

If I read that article right, I just need the ATX-to-AT converter cable? No worries about the power switch?

[X-ray]

I have replaced the PSU on my A4000T twice. The first time was with another AT PSU and the second time was with an ATX PSU (350W) and an ATX to AT converter I bought at the computer fair for a couple of bucks.

Check my pics to see how I did it.

As regards the switch I advise replacing the whole lot in one go. It is more of a pain unfortunataly because you have to take the front bezel off and unscrew the switch panel. Make sure before you get the new PSU that the leads to the switch are long enough (match the length of your existing leads) otherwise you won't be able to connect it!

[marcfrick2112]

Thanks X-Ray! I was planning to replace the whole thing anyway, I was just curious about ATX PSU's having momentary action switches... I have already taken off the bezel and switch panel several times, while trying to find a powerful enough PSU. (I replaced the standard Power LED with a nify blue one, in the hopes that I can get this monster working someday  :-)

[Tomas]

It might be that your new psu is bad as well.. I just had to replace the psu in my pc because it was causing all kinds of strange symptoms. It first started with two usb ports falling out randomly, while there was no issues with stability otherwise.. I really did not suspect the psu at all considering the system was stable otherwise even during heavy load.

A few weeks ago it turned itself of with a snap sound whenever i tried to enter bios or if i used the dvd burner/dvdrom which then lead me to believe it was the psu.
I replaced the psu yesterday and now everything works including the usb ports which has not worked for ages.

Watt does not always mean much anyways since there isnt much of a standard in the PSU world. A good 350watt might for example have more amps per volt line than for example a cheap 400watt psu.

[matthey]

newegg.com has 400W Athena AT power supplies. Plug and play with a 4000T.

[X-ray]

Made a mistake in my previous post, marc frick.
The new switch lead will be on the ATX to AT converter, not on the ATX PSU. Therefore take care when buying the convertor to make sure the switch lead reaches the switch panel on the bezel.

[marcfrick2112]

Thanks everyone for the advice!

OK, let me hear your opinions... Should I just get the 400W AT PSU that newegg.com has, or would I be better off getting a 450 or 500W ATX PSU and an adapter? I only ask because it seems like my 350W is either too weak, or as Tomas said, it may be bad already. I don't know enough about electronics to calculate how much drain this system would put on a PSU ...  :-? I don't want to buy another PSU only to find out it's not strong enough...

This is what the PSU needs to power: A4000T, 16MB mobo, CS Mk-3 w/128MB, 1GB SCSI HDD on 4000's built-in SCSI, ..  Plextor 40x CD-ROM, Yamaha 4x4x16 CDR, Seagate 9.1 GB HDD on CS's SCSI, 10GB IDE HDD for PAR card, floppy drive. Installed cards: Video Toaster 4000, Flyer, Pers. TBC 4, PAR card.

Thanks, Hopefully I can just get this machine working, so I can actually enjoy it... besides, I'm starting to see Molex connectors in my sleep  :crazy:

[matthey]

The newegg.com 400W power supply is not only powerful but pretty efficient. The output is very good for a 400W AT power supply...

+5V@32A,+12V@18A,-12V@0.5A

Compare that to what's shown on your current power supply. Factor in that it's new, reasonably priced and should be plug & play and I don't see much downside. I haven't purchased mine yet so I can't comment on quality or fitment issues but they "should" be fine.

[terminator4]

What do you guys think of using MIOS ATX powersupply and the adapter?

[Damion]

Question: Will it do it with your expansions/cpu card disconnected? A poor contact somewhere can cause similar symptoms, and often it will only show up after the machine is warm. Might want to re-seat the SIMMs (and any other socketed chips), clean contacts, etc... and please forgive me if you've already done so. I had a similar problem recently on an A2K, turned out that the Agnus (seated within a MegaChip) was causing all problems... :/

[marcfrick2112]

Thanks, -D- , Over the last few weeks, I have removed all cards, cleaned contacts, etc. Ditto with the CyberStorm Mk3, while trying to find out what the problem was. Make a long story short, I can boot up OK with either both HDD's, or 1 HDD and 1 CD-ROM, ... It's funny, it doesn't seem to matter what cards (or none) are installed, but the HD/CD drives push the machine (PSU?) too far.... I did reseat the ROM chips, fully cleaned/reseated the CS... I still wonder if it's a power issue, I can have a very stable system, minus 1 HDD and one CD drive, once I connect power to them, nothing, black screen again....

Oh, and you're forgiven  :-D  Seriously, I am grateful for any suggestions...
And now, if you'll excuse me, I'm going to spend some quality time with my 1200T (games and drinking alcoholic berverages .  :pint:  :pint: