520 STe (4Meg upgrade) White Screen of Death Problem

[wyerd]

I ordered the IDE board and TOS 2.06 from Alan but ever since I installed the board, all I get is a white screen on boot.

I first installed the new TOS after installing new pins and put the jumpers in the correct positions for the 30 pin ICs. This worked when I booted. Desktop came up OK and SYSINFO showed everything.

I then had a go installing the IDE board which proved to be a struggle, but after 3 hours, it was in. Great!

Booted and this is when I got the white screen. I then removed the board, but I still get the white screen. I've tried re-seating any socketed ICs, installed new memory and checked the PSU. Everything looks OK. The voltages coming out of the PSU are 5.17v, 5.17v & 12.08v. All the caps look OK, no leaks or bulges.

I'd really appreciate any help and advice as I can't believe I've killed it. Very

Thank you.

[wyerd]

Any hardware Guru's who can help?!

Thank you.

[exxos]

If you have a scope I would check the clock pin on the CPU make sure you have 8mhz there to start with. Also put back old TOS, no mods or anything.. make sure all connections are good. My first guess is the CPU has died..

[wyerd]

Thanks for your reply.

I have tried the original TOS with the same result. Unfortunately, I don't have a scope, just a multimeter. Is there any other way of checking the CPU? Are replacements easy to get hold of?

Thank you.

[exxos]

Yeah, just have a look on evilbay for MC68000 CPU.

http://www.ebay.co.uk/itm/CPU-MC68000P8 ... 5668a8f62f

You could probably find new ones for around $10. Always worth keeping a spare CPU for such occasions

Also make sure none of your CPU or ROM pins have bent under the chip itself. That tends to catch me out once in a while..

[wyerd]

Mines a square shape. I'll see what I can find on eBay over here. Thanks for the tip.

[exxos]

ahh, sorry did not notice you put STE...

I'm not familiar with Alan's board, does it plug in over the CPU ? if so, then it would have bent all the pins on the socket most likely, so they wouldn't be contacting on the CPU anymore..

[wyerd]

Yes, it's designed to sit on top of the CPU. I did make a bit of a mess of the socket trying to get the board in, but the pins do look like they're in contact with the CPU.

I'll get a couple of CPUs anyway. As you say, it's always best to have a few spares.

[exxos]

I would look close on the CPU itself and make sure none of the corner pins have bent over..

The CPU pins may looked connected but they probably aren't.. it only takes 1 pin... I would try plugging the board back in over the CPU and see what happens. I normally keep a strip of small header pins to push behind the pins on the socket to push them to connect on the CPU because of problems like that..

[wyerd]

Thanks for your advice, I appreciate it.

I'll check out the CPU and socket again and take some photos. I'll put them up later if you don't mind glancing your expert eye over them!

Thanks again.

[exxos]

Sure We like pictures on here

[paul92706]

Hi wyerd it's nice to see an Atarian here in the USA here, i am from Sunny Cali. anyhow you came to the right place here for all your questions and problems with your Atari. Lots of good people and very smart and knowledgeable and helpful! may i add.

[wyerd]

Hi wyerd it's nice to see an Atarian here in the USA here, i am from Sunny Cali. anyhow you came to the right place here for all your questions and problems with your Atari. Lots of good people and very smart and knowledgeable and helpful! may i add.

That's good to know!

There aren't very many Atarian's over here. I believe that Atari sold more in Europe back in the day. What kit do you have? Good to know you Paul!
All the best.
David.

[wyerd]

Sure We like pictures on here

You're not going to like these!







Let me know if you need close-ups of a specific area.

Thanks for helping out.

[exxos]

20150317180058.jpg

It looks like your socket is damaged. Looks like the socket pins are not even in alignment with the actual IC. Hard to tell, but looks like the plastic part is bent and skewing the alignment of the CPU pins. I would check under a magnifying glass. But also seems going by the socket image alone, the pins are not even in a straight line. So the only fix would be to change the CPU socket by the looks of it.

[paul92706]

Hi wyerd it's nice to see an Atarian here in the USA here, i am from Sunny Cali. anyhow you came to the right place here for all your questions and problems with your Atari. Lots of good people and very smart and knowledgeable and helpful! may i add.

That's good to know!

There aren't very many Atarian's over here. I believe that Atari sold more in Europe back in the day. What kit do you have? Good to know you Paul!
All the best.
David.

Hi Dave, i have a Atari Falcon CT60/CTPCI and a dead TT030, i am hoping to revive the TT030 so i can implemend the Nova VME ISA Graphics Card to it. Thanks you to!

[wyerd]

It's the angle of the camera. Here's a the area in question:-



or click on this link for a full size image http://kimberlinwyer.com/images/img_1444_O.jpg

But, you could be right and the socket is buggered. It doesn't look like an easy item to replace either......

[paul92706]

Your right Chris, there seems to be a shift there on the socket and IC together, unless my eyes decieve me also seems like someone already had trouble with those pins on the socket contacting the IC as you can see the scrape marks all around, i would definitley replace that socket.

[exxos]

The new image looks better now. Though only thing to do is change the CPU as its the easiest thing to do. If still not working, change the socket and try again.

[wyerd]

OK, I've just ordered a couple of eBay. ETA beginning of next week as they're coming from Sunny CA, Pauls neck of the woods!

I'll be calling on your help on how to replace the socket if the CPU swap doesn't work if that's OK.

Cheers,
Dave.

[paul92706]

OK, I've just ordered a couple of eBay. ETA beginning of next week as they're coming from Sunny CA, Pauls neck of the woods!

I'll be calling on your help on how to replace the socket if the CPU swap doesn't work if that's OK.

Cheers,
Dave.

haha cool! a little taste of Sunny Cali for ya Dave! I have always!!! dreaded replacing those type of sockets, i replaced just about every type of IC and DIP/SIP sockets there is, but not that type, you may need to use a special soldering IRON for that type of Socket, i don't know if an Hot Air gun will get it off, maybe Youtubeing it? good luck buddy! lets hope this solves the problem and you don't need to remove that Socket!

[paul92706]

The new image looks better now. Though only thing to do is change the CPU as its the easiest thing to do. If still not working, change the socket and try again.

It wasn't so easy on the TT030 Daughter board, i had to use a HOT air gun, as it is a 128pin PGA type CPU, but i finally removed it clean!

[exxos]

Yeah removing a socket can be tricky if the person doing it isn't skilled in soldering. I normally heat gun the stuff off, though have to be careful you do not burn the board or end up warping it. Solder sucker and placing a bit of flux on the pins first can get the solder up.. well mostly.. Then I just end up heat gunning it out anyway as can never get all the solder out of the holes Though if I am in not so much of a hurry, I have a hot air station, so i can just kinda blow the solder out of the holes..

Minimal risk would be to get a small pin and bend up each socket pin so you can pull it out with pliers while heating up the pin under the board. Then sucker the solder out of the holes after when the socket is removed.

[1024MAK]

If you have an modern electronic multimeter and some probes that have very fine tips, switch the meter to the low resistance (200 ohm) range, or the continuity range.
Then you can test each socket pin to each chip pin. You should get a low resistance of less than 2 ohms. If you get a higher reading, the chip pin and the socket pin are not making contact.

Mark

[spiny]

Yeah removing a socket can be tricky if the person doing it isn't skilled in soldering. I normally heat gun the stuff off, though have to be careful you do not burn the board or end up warping it. Solder sucker and placing a bit of flux on the pins first can get the solder up.. well mostly.. Then I just end up heat gunning it out anyway as can never get all the solder out of the holes Though if I am in not so much of a hurry, I have a hot air station, so i can just kinda blow the solder out of the holes..

Minimal risk would be to get a small pin and bend up each socket pin so you can pull it out with pliers while heating up the pin under the board. Then sucker the solder out of the holes after when the socket is removed.

out of interest, what air station do you have ? or recommend ? I've just had a look on ebay and they seem to be £30 upwards (chinese ebay) to £80-100 (UK sellers). I watched a few youtube vids and they look like the proper tool to use for doing jobs like replacing a floppy header etc - took me hours with just my iron