Riddle me this

[originalmcblood]

Here is the scenario:

1. Dell Desktop Dimension 4500 with 256 factory installed RAM (at this point the system is working fine)
2. Take out old RAM install new RAM
3. Start it up......
4. Get 3 Beeps
5. LED lights show GYYY
6. HD Spins up
7. Green power light on MB on
8. Fans on PSU and CPU working ok
9. Turn off and take out one memory chip - same results as points 4 - 8 above
10. Turn off and take out other memory chip and replace with original memory - same results as points 4 - 8 above


Have checked and rechecked all cable seatings even though not been touched.

Beep codes and LED lights are standard message indicators for this machine that there is a memory problem. specifically
No memory modules are detected.

I am aware that this is not an isolated problem because I searched the net and found a post describing this exact problem. In fact I "adapted" their post to save me writing it out again as it described the problem perfectly. No satisfactory answer to this post.

I have tried about 7 different sticks of compatible ram with the only difference being if I use a matched pair of 128mb ram the mobo does not give a bleep code and the leds show YYGG which according to Dell means that Memory modules are detected, but a memory failure has occurred.

I'm stumped any ideas.

 

[johnnyq1233]

Have you tried cleaning the ram sockets with contact cleaner?
Other then that it should've worked when you put the original ram back in.
By the way, what new ram did you buy?

 

[originalmcblood]

Did not buy any, salvaged a load from defunct units( but they are compatible with the mobo). My house is littered with components, drives, ram, psu's, etc, stuff salvaged from pc's people no longer want normally 'cos the mobo has gone or they are just upgrading and when I get enough compatible bits to build a system I will build one.
Someone will always want a second pc for the kids or whatever so I give it to them ( as most people do not do much more than web browsing and basic office stuff these normally low spec pc's will do the job). It is kinda like grown up lego but it keeps me amused.

I do not have any contact cleaner but I'll try the hoover (obviously not touching anything on the mobo) I have blown on the mobo to clear the easy dust away but I may need to be a bit more rigorous. This is a salvaged pc that I am trying to upgrade and it is obvious that the case has never been opened since it was assembled, there were dust bunnies the size of tennis balls in there when I opened it.

I'll post and let you know of any progress.

cheers

 

[johnnyq1233]

I wouldn't use a vacuum cleaner on a mobo as they do generate some static.
Compressed air is probably better....and contact cleaner is the best for slots.

 

[frozenlead]

Also try clearing your CMOS.

 

[originalmcblood]

ok cleaned the mobo as best I could without contact cleaner, i'll look into picking some up.

I also removed the CMOS and reset the bios (by removing the CMOS).

still no change. Contact cleaner here I come.

 

[jitpublisher]

^huh? How do you reset the BIOS by removing the CMOS?
Do you mean you remove the battery?

 

[toosober]

You have a bad motherboard. Had the same experience at work with an XW4400 Dell.

 

[originalmcblood]

^huh? How do you reset the BIOS by removing the CMOS?
Do you mean you remove the battery?

yeah sorry!

You have a bad motherboard. Had the same experience at work with an XW4400 Dell.

So has this pc had it then do you think? Salvage what I can and wait till I get another mobo to utilise the components?