A computer components & hardware forum. HardwareBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » HardwareBanter forum » General Hardware & Peripherals » Homebuilt PC's
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

can defective DIMMs kill good DIMMs?



 
 
Thread Tools Display Modes
  #1  
Old October 14th 12, 10:08 AM posted to alt.comp.hardware.pc-homebuilt
[email protected]
external usenet poster
 
Posts: 60
Default can defective DIMMs kill good DIMMs?

I bought some used DDR2 DIMMs to match a pair what I had already. I inserted them into my good PC and it would not boot - no display, not even a beep error code.
So I removed the suspect DIMMs, and still my PC does nothing. Only after replacing the original DIMMs with a third pair did the PC boot.
Next I put the suspect DIMMs in a spare computer, and it gave beep code for
memory failure (has a different mainboard to the other PC). Also tried the original DIMMs that were good, and found they also give bad beeps. So it appears that I got some bad memory which furthermore damaged the original RAM in the nearby slots. I contacted the seller who swears on a Judeo-Christian storybook that they were A-OK when he posted them. They were wrapped in an anti-static bag.
I have been building and upgrading PCs for over 15 years, and have never zapped any modules. And both PCs were set at standard frequency and voltages.
  #2  
Old October 14th 12, 12:13 PM posted to alt.comp.hardware.pc-homebuilt
Paul
external usenet poster
 
Posts: 13,364
Default can defective DIMMs kill good DIMMs?

wrote:
I bought some used DDR2 DIMMs to match a pair what I had already. I inserted them into my good PC and it would not boot - no display, not even a beep error code.
So I removed the suspect DIMMs, and still my PC does nothing. Only after replacing the original DIMMs with a third pair did the PC boot.
Next I put the suspect DIMMs in a spare computer, and it gave beep code for
memory failure (has a different mainboard to the other PC). Also tried the original DIMMs that were good, and found they also give bad beeps. So it appears that I got some bad memory which furthermore damaged the original RAM in the nearby slots. I contacted the seller who swears on a Judeo-Christian storybook that they were A-OK when he posted them. They were wrapped in an anti-static bag.
I have been building and upgrading PCs for over 15 years, and have never zapped any modules. And both PCs were set at standard frequency and voltages.


You can have DIMMs that are so defective, they burn the motherboard.
That's the worst kind of failure. (A DIMM capacitor failing short, on a
motherboard without OC protection, can do that.)

All it takes, is for one DIMM to jump on the bus while the
other DIMM is trying to do that, to cause problems.

So yes, there are a few failure modes that can have a widespread
impact. And, as you note, the testing procedure after an
event happens, can result in multiple other pieces of kit
getting toasted. For example, when you inserted the third
set of DIMMs, and got the "all clear" indication from your
motherboard, if the motherboard was damaged, you could have
had the third set toasted as well. That's if the DIMMs
damaged the motherboard in such a way, as to cause the
motherboard to damage subsequently installed DIMMs. There
have been some pretty expensive "domino effect" failures
people have run into. Usually, people figure it out, after
they've toasted a third set of something :-(

Paul
  #3  
Old October 14th 12, 04:25 PM posted to alt.comp.hardware.pc-homebuilt
Flasherly[_2_]
external usenet poster
 
Posts: 2,407
Default can defective DIMMs kill good DIMMs?

On Oct 14, 5:08 am, wrote:
I bought some used DDR2 DIMMs to match a pair what I had already. I inserted them into my good PC and it would not boot - no display, not even a beep error code.
So I removed the suspect DIMMs, and still my PC does nothing. Only after replacing the original DIMMs with a third pair did the PC boot.
Next I put the suspect DIMMs in a spare computer, and it gave beep code for
memory failure (has a different mainboard to the other PC). Also tried the original DIMMs that were good, and found they also give bad beeps. So it appears that I got some bad memory which furthermore damaged the original RAM in the nearby slots. I contacted the seller who swears on a Judeo-Christian storybook that they were A-OK when he posted them. They were wrapped in an anti-static bag.
I have been building and upgrading PCs for over 15 years, and have never zapped any modules. And both PCs were set at standard frequency and voltages.


What can cause memory to fail other than incorrect voltage, and what
other than the MB's initial draw on the PS to provide that final stage
of regulated memory voltages? All else being normal spec'd. When my
MB was giving me problems, the voltages registered not so far out of
the norm, but what was happening, I think, is the crappy MB capacitors
were straining like all hell. It was to the point of prematurely
wearing out PS units. So, even though everything is reading OK to a
novice looking at programs/sensors reporting voltage setpoints, it's
not really. Things are fluctuating way out of wack at some level
beyond those readings, and, meanwhile, I'm replacing power supplies
every year or two under ****-poor assumptions. When you test a car
battery for instance it's put under a load for a truer sense of how
voltage interacts with current. Not what it displays on a $5
multimeter. Same with those sensors to my way of thinking. How do I
know...I really don't. I just watch for the little abnormalities and
don't dismiss them if they're going to carry over or turn into a
bigger issue. I try and get the stuff right, good components, but
there's always something to watch because I'm a sucker for old-assed
gear when it looks good and priced right. Another thing. No computer
I've owned is ever the same. They've all got their personalities and
sometimes age into something else.
  #4  
Old October 26th 12, 04:41 PM posted to alt.comp.hardware.pc-homebuilt
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,296
Default can defective DIMMs kill good DIMMs?

On 14/10/2012 5:08 AM, wrote:
I bought some used DDR2 DIMMs to match a pair what I had already. I inserted them into my good PC and it would not boot - no display, not even a beep error code.
So I removed the suspect DIMMs, and still my PC does nothing. Only after replacing the original DIMMs with a third pair did the PC boot.
Next I put the suspect DIMMs in a spare computer, and it gave beep code for
memory failure (has a different mainboard to the other PC). Also tried the original DIMMs that were good, and found they also give bad beeps. So it appears that I got some bad memory which furthermore damaged the original RAM in the nearby slots. I contacted the seller who swears on a Judeo-Christian storybook that they were A-OK when he posted them. They were wrapped in an anti-static bag.
I have been building and upgrading PCs for over 15 years, and have never zapped any modules. And both PCs were set at standard frequency and voltages.


It's possible that you have an insufficient power supply, which was at
the edge of minimal power requirements, and adding the additional memory
just took it out over the edge. Since there wasn't enough juice going to
any memory module, they may have all gone bad.

Yousuf Khan
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
4 DIMMS vs 2 Dennis[_7_] Homebuilt PC's 2 November 28th 09 01:07 PM
4 DIMMS vs 2 Paul Homebuilt PC's 1 November 28th 09 08:47 AM
4 DIMMS vs 2 Pen Homebuilt PC's 0 November 28th 09 12:11 AM
No good with 4 DIMMs, any BIOS settings (P5LD2 Deluxe) Prune Asus Motherboards 2 November 28th 05 03:16 PM
Unstable with 2 Dimms Fitz Homebuilt PC's 1 December 13th 03 12:39 AM


All times are GMT +1. The time now is 11:26 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 HardwareBanter.
The comments are property of their posters.