My computer runs Windows XP. It had 512MB of RAM, but I upgraded it a while ago. When I upgraded it, it took a while to make the extra 512MB show by switching the RAM slot it was in.

I have just formatted my HD and reinstalled windows and just happend to notice that it says 512MB again. I don't know when this happened or why, but I did the following tests:

I will call the slots 1,2 and 3 moving away from the processor side of the Motherboard.

1) Ran each stick of RAM in slot 1 on their own and they each run fine.
2) Ran each stick in each slot. Neither work in the middle slot (I'm not sure if they are supposed to. I get the 3 beep error when PC switched on). Only one of the sticks works in slot 3 (I get the beep error when switched on again).
3) The problem has got worse now - I get the 3 beep error whenever I have both sticks in together. i.e the 2nd stick is occupying slots 2 or 3.

It wasn't like this when I started testing.

There is no dust in the slots because I cleaned it out.

I did have a problem with my CPU showing lower than it should have, but the BIOS had dropped the FSB setting to 100mhz instead of 166mhz.

Could something similar have happend to the ram? I don't have any ideas.

Could someone help please.

thanks

What is the model of your MBoard?

Did you verify the RAM compatibility at Crucial.com?

Did you have the computer unplugged when changing the RAM?

Its an MSI KT6 Detla supporting DDR400 RAM.

One stick is PC3200, the other doesn't say. Had it a year or so before, but similar.

They both worked fine before even though I had similar problems when I bought it. I had to fiddle with the slot combination. Now that combination doesn't work.

I haven't verified the RAM at crucial because 1) the computer isn't connected to the net, 2) the RAM sticks don't work together anymore. Only in the fist slot on their own.

The computer was off, but the plug was still in.

There is always power to the MBoard if the computer was plugged in. You may have damaged one or more of the slots or RAM modules.

I suggest you download and use Memtest86.

If you haven't installed the MBoard chipset and intergrated hardware drivers I suggest you do that. Look at the link below to get the drivers.

http://global.msi.com.tw/index.php?...

The power was switched off. The plug was still in. It is a UK plug with power off at the plug.

Memtest says it has to be booted from a floppy drive. I don't have one.

I think I have all the chipset drivers installed. I will try upadting them.

If you had the PSU switch off then that is the same as unplugging. You can get an ISO for CD of memtest86. You will need a burner to make the disk. Below is a link.

http://www.memtest86.com/download.html

If you have 4 RAM slots then install them in slot #0 and #2. (1st and 3rd closest to the processor)

HTH
Bryan

Its got ridiculous now. I can't switch the computer on at all. Any combination with the single ram stick and both.

I don't know whats happening!

Your manual refers to an optional D bracket with diagnostic LEDs? Do you have that bracket? It is both a USB ports and LED bracket. If so, read your manual. That bracket can detect RAM errors.

yes i have the bracket. I will investigate.

I left it for a few days and it all suddenly started working again. Both Ram sticks work in all 3 slots. How ever the system still only show 512mb and not 1gb.

I flashed the BIOS and installed new MB drivers and it is still the same.

any suggestions?

What about the LED bracket?

There are 4 lights on it. They came on in different combinations of green and red when the system started up and then all went green.

I'm guessing that means it is ok?

Have you ever gone to crucial.com to verify compatibility?

yep its fine.

The excerpt below is from the MSI site. It applies to all versions of your MBoard.

Main Memory

• Supports six memory banks using three 184-pin DDR SDRAMs.
• Supports up to 3GB memory size.
• Supports DDR400/DDR333/DDR266/DDR200 SDRAM
Note: PC3200 (DDR400) maximum 4 banks only.

You must have more than four banks of RAM.

Try manually setting your RAM speed to 166 in the BIOS. Ram setting is probably set to auto. You need to change that. That may solve the issue or may not.

I'm not sure what banks means. Its not slots is it?

I remember seeing that it was set to 166mhz last time I looked.

The excerpt below is from the linked site.

“Multibank Dynamic RAM (MDRAM) is a high-performance RAM, developed by MoSys, that divides memory into multiple 32 KB parts or "banks" that can be accessed individually. Traditional video RAM is monolithic; the entire frame buffer is accessed at one time. Having individual memory banks allows accesses to be interleaved concurrently, increasing overall performance. It's also cheaper since, unlike other forms of video RAM, cards can be manufactured with just the right amount of RAM for a given resolution capability instead of requiring it to be in multiples of megabytes”.

http://whatis.techtarget.com/defini...

Yep I understand now. I checked the RAM frequency and it was set to auto, but the minmium was 266mhz and max was 400mhz or in between 333mhz. I tried them all with no change.

The 166mhz was the host clock which I am assuming was the FSB.

The MB supports 6 mem banks.

any more suggestions?

The MBoard only supports 6 banks if none of the banks are DDR400. Then only 4 banks. You have some DDR400. That is the problem. There is no solution other than getting single bank RAM or dual bank DDR333 or less.

For normal computing 512MB of RAM is fine for WinXP. You have a pretty outdates system anyway.

You have not stated what RAM modules you originally had. I assume 2 x 256MB. You aded the 512MB stick. Is this correct? If so, run one 256 and one 512 for a total of 4 banks. Install in the first slots.

I said in the first sentence of the first post that it was 512MB and I added another.

One of them is PC3200 and the other is a year older, so not as fast.

The thing is that it worked for a long time, but I noticed when I reinstalled XP that it showed 512 instead of 1GB which it showed before.

I have made a big mistake in trying to fix the problem now. I changed the CPU multiplyer to 14x instead of auto and the PC will no longer boot :S

I don't know what I can do now :(

I remembered I could clear the CMOS with the jumper to solve my first problem, so I have done that.

It now won't accept any memory again and just does the 3 beep warning.

I'm going to leave it for a few days (like last time when it weirdly fixed itself) and hopefully I will be back to the stage I was 2 posts ago.

Clear the CMOS again with the computer unplugged. Then when booting set the BIOS FSB to auto and the RAM to 166.

How many sticks of RAM and what capacity are each?

There are 2 sticks of RAM. Each are 512MB. 1 is PC3200 and the other does not say on the stick, but its the original one from when I first built it. It has "chips" on each side whereas the PC3200 only has them on one side.

The RAM frequency minimum is 266mhz. I tried it on that as well as the other 2 settings of 400 and 333. It was set to auto as default.

Below is an excerpt from your manual. Try installing the Single sided stick in the slot closest to the CPU and the other next to it. Set the RAM speed to 266.

"Memory Speed/CPU Clock Support Matrix
Note 1: 6 banks support. Please refer to <www.msi.com.tw> KT6 Delta page for the
latest qualified memory list to ensure the system stability".

Ok, thanks. I will try when it starts working again. Its still giving the beep error and won't boot. Last time it did this last week it sorted itself out after a few days.

Unplug the computer and depress and hold the start button a couple of times. Plug in and try.

It makes no difference.

You probably have a defective PSU.

The PSU is on and fine. All the fans start as well as the cpu and cpu fan.

I just get the memory error beeps which is meaning that the cpu can't access the RAM.