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http://translate.google.com/translate?hl=en&sl=fr&u=http://support.dell.com/support/topics/global.aspx/support/kb/en/document%3Fc%3Dca%26DN%3D1011188%26l%3Dfr%26s%3Dgen&sa=X&oi=translate&resnum=3&ct=result&prev=/search%3Fq%3Ddownload%2Blatest%2Becu%2Band%2Brcu%2B%26hl%3Den%26client%3Dfirefox-a%26channel%3Ds%26rls%3Dorg.mozilla:en-US:official%26hs%3DFYQ%26sa%3DG

 

Tom

Hi Tom: That page is what made me think I needed an ecu/rcu. I can't figure out where to download them from.When I do as the article suggests and search dell support-downloads I get a bunch of results in tech articles, but nothing to actually download. Thanks, bnsdd

That article, and all the others I could find after serching Dell Technical support for Resource Conguration Utility, state it applies to Poweredge servers.

 

http://search.dell.com/results.aspx?c=us&l=en&s=gen&cat=sup&k=Resource+configuration+utility&qmp=12&p=1&rf=all&nk=f&sort=K&snpsd=A&ira=False&~srd=False&ipsys=False&advsrch=False&~ck=asrc

Hi JRosenfeld: I guess that means my "memory has changed" at boot is a different problem. Is there any way to pin down if it's a hardware or software problem?Notebook has 256 DDR PC1300 and 128 DDR PC2300 as installed by factory. It alternately recognizes 384 (correct) and 128 (wrong) and sometimes boots correctly. I took the memory out and nothing was obviously amiss. I hate to spend money on a new one if there's a simple fix. As you can probably tell, I'm new at computer repair. Thanks for any suggestions you may offer. bnsdd

From your symptoms, it looks as if sometimes it is only recognising the PC2300. This may be because the PC3200 and PC1300 have different speeds (not sure as I don't have the specs to hand). Although in principle it is OK to mix memory with different speeds (they will then all run at the slowest speed), it is not generally recommended.

 If the PC3200 has a higher speed than the PC1300, it may be that for some reason it is setting the memory bus speed to that for the PC3200 and then fails to recognise the PC 1300.

 

What version is your BIOS?

The latest for Inspiron 5100 is apparently A32. In the downloads page for that it does not mention update to cope with memory speeds, but Bios A31 does mention that that update provides 'Support DDR333(Run as DDR266) on Inspiron 5100'

 

So if your BIOS version is earlier than A31, you could try updating to the current A32 (updates are cumulative, so improved support added in earlier versions will also be in the latest version.

 

Another avenue to explore is to test the memory, as maybe one or other memory stick (the PC1300, most likely as that is the one dropping out) is failing intermittently. Do you have the Dell diagnostics? Or try memtest86

 

http://www.memtest86.com/

 

As a last resort, you could try replacing all the memory with new onesbut this time, all of the same specs.  I would recommend you look at the Crucial.com site, type in your model details and the will offer unitsthat are guaranteed to work.

 

In US:

http://www.crucial.com/

 

For other countries, hover over the US flagtop right and select another (UK or EU: the only differences will be the currency used to show prices).