Another RAM problem

I bought an MPC 4000 second-hand about three weeks ago, that has 1.70 OS installed on it. I have purchased two different makes of RAM, 1 x 256Mb stick of Crucial RAM this one


http://www.crucial.com/uk/store/PartSpe ... 7E&cat=RAM


and 2 x 256Mb of generic RAM, this one

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 51857&rd=1

They are all 256Mb sticks. I have three in all. I have purchased I think the correct spec of RAM as listed by Sean on the MPC forum (CL2,16chips....damned if I can find the thread now though). The stickers on each of the three sticks all report the same specs as well.

Now, if after opening the hood on the MPC, you look at the two available slots for adding RAM, you will see one slot is next to the outer edge of the motherboard. If we call this RAM Slot 2, and the one on the inside RAM slot 1, the following occurs.

Whichever stick of RAM I use in RAM Slot 1, the MPC does not function correctly (the machine reads the RAM etc and loads data into the machine, but the Programs play back all haphazardly, with wrong samples sounding and intermittant samples on wrong keys). I have tried a single stick of Crucial in this position, with the same results as the generic stick.

Now if the same stick is removed and placed in the other slot (RAM Slot 2), the machine works perfectly. Using any of the other sticks in this same slot, the machine also works perfectly (although with only 256Mb sample RAM as there is only one stick inserted), thereby ruling out any problems with the RAM sticks themselves.

If a RAM stick is now added to Slot 1 to max the machine out to 512Mb sample RAM, the errors with the machine return as described above.
I can only conclude from this, that there is a problem with the RAM Slot 1 holder. Would this be the right conclusion? Or could the RAM sticks still be the problem?

Thanks for any advice offered.

Al

I can only conclude from this, that there is a problem with the RAM Slot 1 holder. Would this be the right conclusion? Or could the RAM sticks still be the problem?

Sounds like a problem with the slot that holds the memory. Could be a loose solder connection. Or even too much solder, causing 2 pins to connect.

Well service have had my machine for a good few weeks now, and still seem to be puzzled by the nature of the complaint.

The engineer reckons he had the unit on for a couple of hours and the unit suddenly responded as it should, ie. playing back the samples correctly with 512Mb RAM installed.

Has anyone else ever had this kind of a problem?

The engineer suggested it may be a dry joint between the RAM and the CPU, but if so, what a pig to find!

Anyway, we'll see what emerges.

Al

god bless your mpc man