Solved

One memory card slot not working after soldering to mother board

Posted on 2008-06-16
11
515 Views
Last Modified: 2013-11-10
The slot for the second memory card on the motherboard adjacent the two main chips and the heat sink fan is not working - I had an overheating problem, got a new main heat sink assembly and fan and soldered a jumper wire and loop across HS2 on the board from the top.  The original card in the second slot (adjacent the heat sink devices and the HS-2 slot) did not work when I restarted the machine; removing that card allowed the machine to boot up and operate, although slowly (with only 256 MB).  I replaced the original and second cards with Kingston 1-G cards, but the second card slot does not work either.  Nothing looks amiss from above.  Could my soldering the jumper across HS2 have goofed up something under the motherboard, or is there likely another problem?  Please advise on analysis and repair.  Thanks.
0
Comment
Question by:Patent_Atty_Chgo
11 Comments
 
LVL 31

Assisted Solution

by:Frosty555
Frosty555 earned 100 total points
ID: 21794865
How close was the place you soldered to the memory slot? And did you use a soldering heat sink when you did the work to prevent heat damage to the rest of the board?
0
 

Author Comment

by:Patent_Atty_Chgo
ID: 21795506
The HS2 pins are a good 3/8 to 1/2 inch or so from the memory slot.  I used a very small soldering iron with a pin tip, so unless solder ran beneath the board I can't imagine there was damage by heat; the initial melting of the HS2 pin connections was likely as hot....  I did not use a heat sink on the board, but tinned the wire ends and the sockets to minimize heating duration.  
0
 
LVL 26

Accepted Solution

by:
PCBONEZ earned 200 total points
ID: 21798110
Check for solder hairs or droplets. (Bridging a gap.)

Check that you didn't scratch a solder trace/run on the board with something while you were handling it. (Everywhere, not just at the work site.)

Check on the other side of the board from where you were soldering to see if any SMD devices shifted on their pads. (SMD are those tiny things.)

A magnifying glass and a small flashlight can help big time with some of those above.

Clean up the site after the work with isopropyl alcohol (Rubbing alcohol. I use 91% which has 20% less water than 71% and is just as easy to find.) and an old tooth brush, que-tips, or similar. You want no flux left behind.

If you didn't remove the CMOS battery while you were working you might want to reset the CMOS. (And maybe re-flash the BIOS too.)

Motherboards are thick PCB's. You generally want to use a hot iron (40-60 watts) to minimize the time heat is applied. Warming the site slowly over a long time actually allows the heat to travel further through the PCB than using something very hot and getting it over with quickly.
Also want to use small diameter solder. It takes less time to start flowing and thereby minimizes the time heat is applied.

.
0
 
LVL 91

Expert Comment

by:nobus
ID: 21801653
did the seconfd slot work before you started? if not, it may just have been bad all the time...
0
 

Author Comment

by:Patent_Atty_Chgo
ID: 21803348
The full memory, both cards, was fine before the system overheated and pulled out the heat sink loop at HS2 on the motherboard.  I replaced the main heat sink and fan and soldered a jumper wire across the HS2 contacts as suggested in previous posts; when the system started up again I got the memory error message, and that cleared when I removed the card in the second slot.  So it was either the system heat or the soldering that disabled the memory slot - a new 1G memory card also did not work when the system started up, but the system works fine with no card in the second slot and a 1G card in the first slot.  Any ideas?  The motherboard must be removed from the case to see the underside - a major undertaking....
0
How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

 
LVL 91

Expert Comment

by:nobus
ID: 21804059
it's the only thing to do : inspect your work closely, and double check for shorts; clean it out also (maybe debris fallen in to it..)
0
 

Author Comment

by:Patent_Atty_Chgo
ID: 21804818
Yes, I worry about where the original 2-pin and loop device at HS2 has gone to - can't find it anywhere in the case!  Thanks.
0
 
LVL 91

Assisted Solution

by:nobus
nobus earned 200 total points
ID: 21804858
>>   can't find it anywhere in the case!   <<  you better find it...cause of trouble ahead
0
 

Author Closing Comment

by:Patent_Atty_Chgo
ID: 31467659
A local technician has advised that 1G of memory is plenty unless I'm doing video editing or such, so I'll not worry about the 2nd memory slot.  Thanks!
0
 
LVL 91

Expert Comment

by:nobus
ID: 21805053
that depends on the OS you use; with XP i agree ; but with Vista 2 Gb is suggested...
0
 

Author Comment

by:Patent_Atty_Chgo
ID: 21805155
Based on what people say, I'll stick with XP for as long as possible!  Thanks again.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Memory (not to be confused with Hard Drive Space) can greatly increase the performance of a computer. Each version of Window has greater demands on memory. My personal recommendation to get decent performance out of a machine is as follows: Windows…
As you can read I recycle all my old hardware and the time has come that my power supply of 200 Watt cannot provide enough power for my backup server. I have lots of Compaq power supply's laying around, so I figured to use one of these PSU's. I t…
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, Just open a new email message.  In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.

707 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

13 Experts available now in Live!

Get 1:1 Help Now