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#1 2017-02-03 12:07:05

LazarusNine
Member
From: UK
Registered: 2015-03-07
Posts: 68
Website

Sourcing PM 5400 Video Issues

I recently purchased a Power Mac 5400/180 that was exhibiting video issues (see photo). At first, I thought it was likely caused by bad caps on the analogue board, but a member on another forum suggested that it might be related to VRAM on the logic board. I've pulled the logic board and noted that there are no VRAM DIMMs present (there's no slot for them). Any suggestions as to what might be the culprit for the distorted video? Is this a cap job on both the logic board and AB, or something more? Thanks!

Image%2032_zpsc2gbupbt.jpg~original

IMG_0573_zps6zqtym9m.jpg~original

IMG_0575_zpsr2wgblyq.jpg~original

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#2 2017-02-03 14:27:25

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

Looks like you've got an external (mirroring only?) display cable/connector option installed. Hook one up and use it as a test to see if it's a logic board or AB issue?

edit: what the heck is that white block on the ComSlot card? I'd assume so, but did you pull that card a/o the video setup to see if either is the problem? The tuner card messes with video big time.

Last edited by jt (2017-02-03 14:35:37)

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#3 2017-02-03 15:29:12

LazarusNine
Member
From: UK
Registered: 2015-03-07
Posts: 68
Website

Re: Sourcing PM 5400 Video Issues

Hey again. Thanks for the pointers, jt. So, I think it's safe to say it's not the analogue board! Must be the logic board - somewhere, somehow. I removed the two cards you mentioned, but the problem persists.

IMG_0578_zps01yi0uef.jpg~original

I did notice a little bit of battery residue - not sure if it's enough to be a contributing factor.

IMG_0580_zpsia32iary.jpg~original

Last edited by LazarusNine (2017-02-03 15:48:16)

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#4 2017-02-03 17:02:42

macdrone
Member
From: Rainier, Or
Registered: 2014-05-25
Posts: 231

Re: Sourcing PM 5400 Video Issues

might need new caps and a cleaning on the motherboard.

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#5 2017-02-03 17:04:24

macdrone
Member
From: Rainier, Or
Registered: 2014-05-25
Posts: 231

Re: Sourcing PM 5400 Video Issues

Since the video is garbled and that battery corrosion is close the the external video connector you may be on to something.

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#6 2017-02-03 17:08:04

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

I'd say so, look at the mirrored image on the CRT, it's whacked way out of sync. There are two "portrait mode" images squeezed together on the screen.

For the next test, do a screen shot to see if the VRAM dump comes up good. See if you can manage do copy it to floppy. If it's clean, that'll help eliminate a few jumped at conclusions elsewhere. wink

Last edited by jt (2017-02-03 17:20:12)

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#7 2017-02-04 14:06:46

LCGuy
Administrator
From: Sydney, Australia
Registered: 2014-05-13
Posts: 815

Re: Sourcing PM 5400 Video Issues

jt wrote:

edit: what the heck is that white block on the ComSlot card? I'd assume so, but did you pull that card a/o the video setup to see if either is the problem? The tuner card messes with video big time.

That white block is part of the modem - clearly this machine has a CommSlot modem installed. (pull it out and replace it with an ethernet card, you'll get ethernet networking without having to give up your single PCI slot, plus if you pull out the plug that covers it you'll now have use of the modem port on the back) PCI Winmodems for Windows PCs have a similar (but much bigger) sort of arrangement.

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#8 2017-02-04 14:32:58

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

LCGuy wrote:
jt wrote:

edit: what the heck is that white block on the ComSlot card? I'd assume so, but did you pull that card a/o the video setup to see if either is the problem? The tuner card messes with video big time.

That white block is part of the modem - clearly this machine has a CommSlot modem installed.

BLECH!!!!! yikes Gimme a stick, I'll kill it! No wonder I didn't recognize the evil thing.

I'm very curious to see results from the screen shot test for the video memory/VRAM Dump. If it's OK, we'll have narrowed borkage of that logic board down to the circuitry from VRAM to RAMDAC a/o traces from there to the fork in the display linkage. Dunno, wondering about how to isolate the problem to either side of the RAMDAC.

Doesn't really matter though. SMT fix for one big IC would a lot better than fooling with whatever VRAM ICs might be involved if that's the problem child..

Up side to your problem: transplanting a 50MHz 5500/6500 board with a better RAMDAC is by far the easiest fix!

Me, I'd probably add a side order of 15" Trinitron hack to the main course. big_smile




edit: forgot about the case hack for two PCI slots, doing that in a desktop RoadApple box. But even I wouldn't touch that Black ABS.

Last edited by jt (2017-02-04 14:38:30)

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#9 2017-02-04 16:23:58

macdrone
Member
From: Rainier, Or
Registered: 2014-05-25
Posts: 231

Re: Sourcing PM 5400 Video Issues

If you want I may have a spare 6500 motherboard you can change the back panel off of and be a bit of an upgrade.

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#10 2017-02-04 23:11:07

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

If he's not interested (or in the UK, can't figure that one out) I could sure use a complete 6500 drawer assy. Hast need of 1400 trade goods or any other?

edit: saw over yonder that he's in the UK. wink

Last edited by jt (2017-02-05 14:37:46)

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#11 2017-02-05 18:05:36

macdrone
Member
From: Rainier, Or
Registered: 2014-05-25
Posts: 231

Re: Sourcing PM 5400 Video Issues

I could use a 1400 processor upgrade, maybe skins that came with the clear cover.  I will pull 1 out and get it ready, I have a few I think.

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#12 2017-02-05 22:36:44

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

Cool! I'll probably have to give you a side of MoBo to go with that 166MHz card. I think I can find one that's not already spoken for in the stack. Inventory's in the notebook at work, didn't bring it home for lunch. hmm

I've got a couple of skins, that I know, but I'll have to find my partial set for one that doesn't go with the lid it cams under.

Last edited by jt (2017-02-05 22:38:55)

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#13 2017-02-05 23:16:30

LazarusNine
Member
From: UK
Registered: 2015-03-07
Posts: 68
Website

Re: Sourcing PM 5400 Video Issues

macdrone wrote:

If you want I may have a spare 6500 motherboard you can change the back panel off of and be a bit of an upgrade.

That's a very kind offer. I'm very interested and happy to pay for the added shipping to the UK as well if the need arises. I'll see if the capacitors arriving in the next couple days will do the trick. If not, you may indeed hear from me!

jt wrote:

edit: saw over yonder that he's in the UK. wink

It's true!

Last edited by LazarusNine (2017-02-05 23:18:26)

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#14 2017-02-06 14:13:39

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

That's cool, hopefully you'll get a better deal from bibilit for one shipped from Paris. I really only need the drawer face, which you don't. If you're ever getting a package shipped from across the pond be sure to let me know. I can send whatever trinkets you might need  from my dragon's hoard to you if you'll transship a small package to cosmo for me. wink




< struggling with the very notion of giving in to the pressing need to exit Smaug mode. hmm >

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#15 2017-02-11 08:22:58

LazarusNine
Member
From: UK
Registered: 2015-03-07
Posts: 68
Website

Re: Sourcing PM 5400 Video Issues

macdrone wrote:

If you want I may have a spare 6500 motherboard you can change the back panel off of and be a bit of an upgrade.

Hello macdrone! Bibilit over yonder managed to find a 6500 logic board and has sent it. So, just waiting on that to arrive. Assuming all goes well, I should be good to go. Thanks for the offer, though, and I'll definitely keep you in mind if things don't work out with this board. Hope all is well. Thanks to everyone for the help so far. Updates forthcoming!

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#16 2017-02-11 15:51:36

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

HEH! I hope the bibilit board works out for you. Looks like I might be sending a (hopefully working) PartsBook1400csxxx w/tidbits out yonder. wink Worse comes to worse, I've got a few of these boards too. wink

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#17 2017-02-12 20:12:15

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

Never mind, it seems I may have been pursuing Gazelle upgrades of dubious value to my mainstream hacks for many years. roll

Got Alchemy in twin slot drawers? neutral

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#18 2017-02-16 19:39:39

LazarusNine
Member
From: UK
Registered: 2015-03-07
Posts: 68
Website

Re: Sourcing PM 5400 Video Issues

We can consider this matter resolved! Thanks to bibilit's generous provision of a 6500 board. Also, thanks to others who offered to help me source a replacement logic board. While the 5400 board might work with a bit of effort, this was a very cost-effective solution that satisfied my desire for instant gratification. The 5400 is now running at 250MHz, which is also pretty cool. =P

IMG_0685_zpsaemezhj6.jpg

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#19 2017-02-16 21:10:05

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,407

Re: Sourcing PM 5400 Video Issues

It's also a 25% bump in System Bus Speed on top of that processor clock upgrade. It should be quite a bit snappier overall performancewise.

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