MPC not detecting full Memory Upgrade

I installed an additional 256 MB Memory stick in my MPC, for some reason, it's only detecting 128mb of it though... It's still more than before, so I'm not throwing a huge fit over it, I'm just wondering why its only detecting 400 total. Anyone else had this problem?

No, I didn't use the Kingston memory, but I used a 256mb PC-100 100mhz DIMM Desktop stick from another company.

so now you have two 256mb sticks installed? can you give us the full specs of the ram? try installing one at the time and see what happens. also try swapping sockets. it should be pretty easy to suss out where the problem lies.

one other thing: when i maxed the ram in my machine i had to clean the ram sockets a few times (de-oxit and compressed air) before it started working correctly. something about 10 years of collecting dust...

- jim

I forget the exact term but you need double sided ram.

I installed 512mb but only half was showing up so I got it replaced. The seller claimed that the single and double sided had the exact same part number, which I find hard to believe.

Either way, if that's the issue you should get it swapped because it will just annoy you if you don't get it maxed out! I think it cost me £15 in total.

Great suggestions guys, I will try both.

Here is the spec: 256MB 100Mhz/PC100 168-Pin DIMM

ECC: Non-parity
Buffered/Registered: Unbuffered

I did slide one stick in at a time. A few times I had trouble with the memory detecting at all, I had to re-seat it a few times, I did swap the slots. Due to the trouble with it detecting, and doing so after a firm re-seat, a cleaning would make sense. I will get a can of air over here in the next couple of days.

As for the single sided-ram/double sided... this could also be a possibility. While "Double Sided" ram many times is actually on both sides of the stick, the technology (Ram separated in 2 groups, instead of 1 big one), CAN be on one side. Not sure what this new stick is, BUT, it does only have chips on one side of it. Wither its actually functioning as a single or double group, not entirely sure, but based on visual implications, I would say it is a single. I'll keep my eyes peels for different one. Thanks fellas, I'll try this out, let you know when I solve it.

could be bad memory
or could be bad motheboard


good luck

coupla' things:

thing 1: you're gonna want some pcb-friendly contact cleaner. i doubt compressed air alone will net you much, if any, improvement.

thing 2: doesn't the mpc need ram with a specific CAS latency rating? as in only CL2 will work?

this is what i installed in my machine: http://www.ebay.com/itm/ws/eBayISAPI.dl ... OC:US:3160

i can attest to it working flawlessly and complying with all mpc requirements.

- jim

The Clock Latency is often overlooked on MPC RAM, but any ram that didn't work for me (4000, 2500, 1000) in every case did NOT list the CL number. For my 4000 I actually ordered the exact Kingston stick always mentioned. But no CL rating and the 4000 recognized nothing.

So, I found this: 256MB SDRAM PC133 168-Pin DIMM (16-Chip) on Amazon for $5.

I did notice the original addon ram I tried to put in, did only have 8 chips, and was single sided. So I got the one with 16 chips that was double sided. Popped it in... yep, sure enough, it detected it all.