I have a Dell Dimension 4700 running Windows XP and the latest (?) -- A10 -- version of BIOS. I tried to upgrade my memory by inserting four 1 Gig memory cards in all four slots. Two of the slots (numbers 1 and 3) have white clips on them and the other two (2 and 4) have black clips. When I insert the new memory cards into the white slots, everything works fine. When I insert the memory cards in both the white and black slots my computer exhibits really bizarre behavior. It doesn't exactly start up. It sort of rustles a lot (there aren't even beeps) and then the monitor screen displays either incomplete snippets of the startup screen, or static black and red vertical lines, or moving green vertical lines, or other random-seeming junk. At that point the computer is sort of running, but not really. It's very quite and I can't turn it off using regular procedures. It doesn't even turn off when I press the button. I can only turn it off by cutting the electricity -- the power supply. So, I'm thinking it's not actually running or starting.
I've tested all four memory cards in the white slots and the cards all appear to be good. I've also tried putting two of the new cards in the white slots and my two old cards in the black slots and gotten the same bizarre behavior. Basically, as long as I don't touch the black slots everything is good, but then I only have 2 Gigs of memory.
The new cards were sold to me as being explicitly for Dell Dimension 4700. They are
1 GB Module DDR2 PC06400 CL=5 non-ECC Unbuffered DDR2-800 1.8V 128 Meg x 64. (I don't know what most of this means, but I'm assuming somebody does.)
Sometimes upgrading memory seems to be an arcane art. The Dimension 4700 has a dual channel memory controller; the different colors on the memory socket latches are indicators of which slots are supposed to have matched memory modules. You should keep the original memory together and the new memory together. There may still be a problem, however, if the characteristics of the new and old memory are very different. The controller is supposed to fall back to the speed of the slowest memory because all the memory must be run at the same speed.
You seem to have gone through most of what I would do already; tried the new memory in the first pair of slots and the old in the last pair. Did you try it the other way round, leaving the original memory in the original slots and placing the new memory in the last pair? After that, the only thing I can think to do is to reset the CMOS by removing the CMOS back-up cell for five or ten minutes. Unplug the power, push the power button and hold it in for ten to twenty seconds to discharge the power supply keep-alive voltage, remove the CMOS battery, push the power button and hold it in for another ten to twenty seconds to discharge the back-up battery circuits, replace the battery after the ten minute period has expired, connect everything and try again. Sometimes forcing the computer to re-detect all its devices helps with this sort of problem.
If that doesn't help, the specs on the old and new modules may just be too different to allow the memory controller to find common operating parameters.
Jack, let me clarify. I've got two identical sets of the new memory. I don't have to use the old memory at all. I've got four cards of 1 Gig each. So, two of them (any two) work in the white set and when I put additional two in the black set it goes haywire.
I did misunderstand that part, but my suggestion to reset the NVRAM is still a good idea. Sometimes these problems are caused by a mismatch between the stored configuration of the machine and what is actually in it. If resetting the NVRAM doesn't do it, then I am as puzzled as you.
EDIT: One other question I neglected to ask; when you install the RAM you can go to System Setup and see what the controller thinks of your memory. If the memory is sufficiently matched in timing your BIOS will report that the memory is in dual channel mode. Otherwise you will get single channel operation. Memory vendors will frequently make a match for you so that you can purchase a set of modules that are guaranteed to match closely enough that your computer will run in dual channel. I don't think this has a direct bearing on your complaint but operation in single channel mode will slow things down a bit.
2 sets is not the same as 4 pieces of identical vendor memory. Some Vendors do not play nice together.
Are they ALL the same vendor and All the same speed and ALL the same wait states?
32 Bit os is limited to 3.25 to 3.5 gigs of useable ram.
Uh, I feel really really stupid, but, after I went and tested all the slots separately, including the black ones, and then put everything in again, the four cards together worked. Apparently, I'm guessing, I didn't put them in securely enough before, although, in my defense, I really did check for this several times. Thanks for your help, guys. Oops (sheepish grin).
Now I have a different problem though. It's only reading 3 gigs of memory. A quick Internet search shows that this is a 32 bit operating system limitation and that I have to upgrade to a 64 bit system to effectively use all four cards. :-/.
I know this is an old question, but XP is 32bit, and can only utilize 3gb ram, putting in more is a waste.
I've read this whole feed and it seems to be helpful. Although, I would like to venture out (mostly to save money) and fix my computer myself. I'm very good with software, but I've never messed with the inside of a cpu before except just to see what was inside. My computer is a 4700 as well, but I have Windows 7. The guy that fixed it recently for me replaced Windows XP (which is what I had) with windows 7. Should I take some lessons from Youtube and try to figure out what the motherboard and all that junk is all about so I can install more RAM *much need* on my cpu, or should I pay money to get it installed for me? (I don't want to break my computer.)