DDR2 Failure in PC

[annie0000]

How likely is it that both DDR2 units in a PC would fail simultaneously and what would be the likely cause?

Just trying to work out if it is worth buying more to put in or if there is an underlying problem that means it will be wasting money.

Thanks

[AlBags]

Zero .. basically .. unless a power supply fried them due to over-voltage.
Then the CPU would probably shut you down anyway.

Why do you suspect this?
CRC errors opening zip files maybe? That's a good sign of bad memory.

[annie0000]

It's actually a problem I posted about weeks ago Al - the boy's PC just suddenly stopped working. Fan is on full blast and there is power but no signal to the screen etc and it is isn't booting. Fiddled around a bit over the weekend and discovered that the diagnostic lights are basically telling me that it is a problem with the memory. I have two 1gb thingys and 4 slots. I followed advice from the Dell forum which was to take them both out and try them individually in Slot 1 and see if it boots - neither worked :o(

Prior to this we tried connecting another hard drive, another screen and swapping the internal power cable - none of which helped. It has an enhanced graphics card but I have tried the screen with both the normal and enhanced and makes no difference.

I don't want to go and spend money on new DDR2 thingys for that not to be the problem. There is no sign of any damage or shorting or anything inside the PC.

[SlackAlice]

Highly unlikely that both memory modules would go defective together. Take out both sticks carefully wipe the contacts with either meths or alcohol based cleaner. Check the contacts visually for any defect. Check the slots for any damage or rubbish.

I assume the sticks were fitted in slots 1 and 3, try slots 0 and 2 either singularly or together. If no better, only other idea is to try them in another pc.

[annie0000]

Hi Alice - the slots from bottom to top are numbered 1, 3, 2, 4 and the units were in 1 and 2 - will it still recognise them if I don't use slot 1? I'll give that a try though. Unfortunately I have no other computer that they fit in. We have 2 other pc's and they both take just DRR units so cant swap across anything. So frustrating!!

[SlackAlice]

Showing my age, whenever I've looked at pc motherboards they've labelled them slots 0,1,2,3. Also you had to fit them in slots 0 and 2 preferably for two sticks and slot 0 for single stick, but you could use 1 and 3 as well.

As AlBags states you may have a power spike from the power supply and fried them.

[AlBags]

The slots you use them in is actually governed by what the motherboard supports .. It is usually in the very first (0) and another slot .. the other depends on the mobo .. Some need in a defined slot to allow dual-channel memory mode to work.

What is it ACTUALLY doing on boot-up .. How far is it getting?
Can you press the correct F-key to get into the BIOS?

[AlBags]

There is also a way of displaying (on hover popup) the latest post in each of the Topics on the left ..
That would be good to hover over .. and see latest post inside them, without expanding all the time .. or hoping to see in the latest posts list.

[AlBags]

Oops (posted in wrong thread!)

[annie0000]

Thanks again Alice.

Hi Al, It doesn't get anywhere at all. There is no display to the monitor. There is power to the machine and the fan works at full blast. It's a Dell Optiplex 745 - it has diagnostic lights on the front and lights 1, 3, and 4 are lit which, although Dell support doesn't give exactly that combination for some reason, seems to be indicating a memory problem.

Is a power surge something that came from within the machine itself or would it be stopped by a surge protection on a multi socket lead? Sorry for the stupid questions, just trying to get this fixed for my wee boy at the least possible cost.

[annie0000]

Thanks methyl - no beeps :o(

Yes, I have been on the Dell website and have asked a question on the support forum and the chap there also believes that it is a DDR2 issue based on that light combination. But I am still trying to find out what caused it so as to decide if it worth forking out for the new units.

[AlBags]

There is not going to be a definitive answer ..
No graphics output at all is unusual .. but not impossible.
There is still a choice ..
Graphics Card ... How is it connected? VGA or DVi?
Motherboard taken out for some reason like power supply
memory (unlikely, in my opinion)

I think you will have to take it locally to a PC guy .. ask them to have a look and see what they think. I don't think anyone here can help you much more.
Personally I don't believe the lamp code.

[Why_Sign_Up]

I had the same issue with diagnostic lights on my optiplex 745 desktop. lights 1,3,4 were green but no go. I added a new pci-express 1x video card and that seemed to be the cause of the 1,3,4 lights green. after removal and the problem went away. So now I need to find a better older card on ebay that Dell recommends will work with this system. ***it did not matter what slots memory in but it booted up fine without new video card.*** I have memory that came with system: M378T6553EZS-CE6 (made by Samsung 2 x 512mb). You should look on Newegg and read reviews(to find others) who purchased better compatible memory if you do not want to use factory memory.

[annie0000]

Thanks all. I removed the enhanced video card and hey presto! back in business - boy v.happy and not upset yet that he has had to downgrade the graphics a bit on minecraft to reduce any lag.

I love this site, so many helpful people :o)