A31p: Front Memory Slot Has Quit Working.RESOLVED!!

[olex126]

The front memory slot on my backup A31p is refusing to recognize any RAM. RAM is definitely good, tried in the rear slot and is identified, tried in a T30 and worked in both of those slots. (These were 1 gig modules, tried 512 modules with the same result.)

Took the machine apart to the point where I can get at both sides of the RAM modules on the motherboard. Inspected the board and soldering joints with a tiny metal pick, good lighting and a 10x jewellers' loupe, Couldn't find any obvious broken joints. Did a bit of continuity testing with a meter, but am not exactly sure where I should be probing.

No water or coffee spills, no drops to the floor that I'm aware of.. basically the front slot has just stopped seeing memory. (component failure somewhere else along the line?)

Any hints, suggestions, tips, or tricks?

Model is 2653-CU5, Board FRU 26P8430 (64mb video, sec. chip..of course, it has to be the top end EXPENSIVE board on ebay!!) I have a known good 26P8399 board (64 mb video, no sec. chip) I can sub if I have to, but I would much prefer to see if I can trace what has caused this problem.

Thanks in advance for any advice. I'm pretty handy at soldering/de-soldering, but it would sure be nice to have a circuit printout!

Regards.

Dave

P.S. I'm always on the look-out for the 26P8430 board or any systems with this board in them. Let me know if you have anything available.

[tbartold]

Inspected the board and soldering joints with a tiny metal pick, good lighting and a 10x jewellers' loupe, Couldn't find any obvious broken joints.

Sorry if I'm asking the obvious, but are you sure there are no hairline fractures in the board or traces, not just the joints?

[olex126]

I'll start checking the traces that appear to be connected to the memory slots when I get home tonight... hopefully something will show up there.

Dave

[olex126]

ISSUE RESOLVED!

As I was tediously probing front memory slot traces (and finding everything connecting) I inserted a memory module in the front slot... it seemed to slip in rather easily, something which I had not noticed before. Inserting the memory into the rear slot introduced a slight bit of resistance... HMMMM.. loose slot maybe?

I semi-assembled the planar back into the base, enough to fire things up. Inserted both memory sticks into the connectors and then placed a piece of foam inside the memory cover door to put some slight pressure on the front memory stick before I screwed the cover back on. Booted into BIOS and BINGO! I now had my 2 gb memory back!

Dis-assembled everything again, and since I had it apart, installed new GPU pads for the video chip. Installed back together completely and then measured and cut a small piece of packing foam (slightly smaller than the memory chip.. turns out the perfect fit is .140" thick. Used a couple of drops of hot glue to secure the foam to the memory cover, and installed. Booting up produced my lovely 2 gb of memory.

I've been using the TP now constantly for the last 2 days, running 12-14 hours/day, carrying it around to different locations.. fires up and sees both memory modules every time. Notebook Hardware Control shows no difference in any operating temperatures or other variables.

I realize this is not a permanent fix, but until I get time to desolder the old memory holder and install a new one, it will do for now.


Hope this may be a starting point for anyone else who runs into the same problem... I remember a T30 some time back with finnicky memory slots... should have remembered that before I started to tear apart this A31p! (Too soon we grow old and too late we grow smart!)

Regards.

Dave

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