I got some RAM to upgrade my desktop pc (Dimension 8400, circa Apr 05, P4-HT 3Ghz). The extra RAM is 2nd hand but it came out of a Dell of similar vintage and should work. I've got existing 2x256mb RAM and wanted to add 2x512mb RAM but I've tried various combinations and can't get it to work.

The pc boots ok, I can go into the motherboard settings and it recognises it but as soon as it gets into windows it hangs at the login page. On the user login page, you have no controls of any sort (I'm using a MS wireless keyboard/mouse set up if that matters). I've resorted to going back to the original 2x256 RAM combo.

What's likely to be the problem? The RAM? The wireless controls? The USB ports? Is it a locked down Dell OEM WinXP that won't let me upgrade the RAM?

I'm planning on changing the HD and putting a, ahem, *fresh* copy of Win XP on there at some point anyway but I'd rather get this working if I can before I do that from scratch.

Well, if the only thing you've changed is the RAM, then it must be the problem? If changing it back clears the issue, I think it's pretty definite.

Phil

Have you tried directly replacing the 2 256mb ones with 2 512mb ones, and leaving the 256 ones out (for now)?

Have you tried adding just one of the 512mb sticks, and then if that doesn't work, try the other one? There's a chance just one of them might be dodgy?

Those would be my approaches.

My guess is the ram is duff, that said it could be the power supply not up too the job of supply juice,

Or a bios update may cure it as the board maybe kind of unaware that 2x512 exsists.

Any idea of the clock speeds on the 2x256 are they the same as the 2x512 something like pc3200 or pc2700. If the newer sticks are lower rated that could be your issue.

HTH

Tried all sorts of paired combinations:

2x256 + 2x512

2x512 + 2x256

2x512

I thought they were supposed to be in pairs so haven't tried singly, may try that

Off the top of my head I can't remember the exact type but I think they're marked the same and both branded (Samsung I think)

I'm confused as the BIOS says hello to all the RAM but XP says no thanks

I bought the 2x512 off a member here for buttons and if he said they worked beforehand I have no reason not to believe that

It's only the really old stuff that needs to in pairs.

Sounds odd for a memory problem. Normally any memory faults will stop things booting, normally you won't get past the BIOS.

But it's still the most likely answer.

Try the old stuff again just to make sure that windows just hasn't gone wobbly.

I've seen similar issues with duff RAM. The BIOS only checks that something exists each address. It's only when you boot the OS that things start being written and read at any speed.

Phil

In that case, I'll try all 4, 1 at a time to what works and what doesn't when I get a chance.

Edited 27 March, 200917 yr by daiking
awful grammar

sounds like windows crashed.. the keyboard should work if the bios sees it.. does the caps-lock light come on when pressed when its in win? thats a surefire test to see if its locked up or not.

As already said it sounds like one of the sticks may be duff... get hold of memtestx86 to narrow it down

Memtest86+ - Advanced Memory Diagnostic Tool

This will help you determine whether you have a mem issue (i.e. faulty stick), or a compatibility issue...

There have been some other reports recently of keyboards not working. My main PC at home did this a month or so ago - I ended up reinstalling the machine. I know someone else who suffered this problem two days ago. I am working on the assumption that Windows locks up with just the original RAM in it now as well? In my case, I was using PS/2 keyboard & mouse, and as soon as a press a key to enter my password it locked up, but prior to a key press, the mouse worked fine.

okily dokily folks, I've taken all the RAM out and am trying a single 512mb stick in the first slot

BIOS recognises the change

Windows boots to login screen

Mouse pointer bang in the middle

No response from wireless k/b and mouse

Plug in a wired USB mouse - full mouse control, can click on user name but no k/b to type password - assume it would work and RAM is ok unless its affecting the USB device.

So I seem to have narrowed down the problem but wtf? Why won't it work? flat batteries? Just tried new ones, no help.

Just gone back to original configuration and the wireless stuff works

Anyone? :confused::confused::confused:

Just gone back to original configuration and the wireless stuff works

Anyone? :confused::confused::confused:

Some kind of conflict?

If you have a Linux LiveCD then you could try booting from that into linux and see if everything works ok.

You may also need a bios upgrade, I remember something simillar with an old Dell machine and a bios update fixed a simillar issue.

i've managed to put in one of the 512 sticks as well as the 2x256 and so far its working.

will swap the 512s to see if this last one is the dodgy one.

oh ffs, all 4 sticks of RAM are in and the ****ing thing works

Why wouldn't it do it weeks ago, why wouldn't it do it earlier on, why could I replicate the problem from proved working USB ports, why would the wireless keyboard work in the BIOS setting but not windows. Grrr

Must dash got a month of downloading to catch up on.

There is an option to reset all device addresses in most bios, which will assign a new address to the devices.