Memory size problem

Gigabyte GA-5SMM motherboard
AMD K6-500MHz CPU (jumpers set right)
80 GB WD HD
Windows 2K
D-Link wireless PCI card
8MB shared onboard video

I picked it out of a junk pile, updated the BIOS, replaced the HD, and loaded W2K. Booted it up and ran Everest and checked the specs. Found 64 MB PC100 memory, I decided an upgrade was in order. Bought 256 MB PC133 used from a local used shop with a good rep and installed it. Under BIOS and Everest, it shows 128 MB. I took it back and the clerk checked it on their test rig and he got the full 256 MB, and it passed Memtest. I have 7 days return policy, but I don't believe that will solve the problem. I suspect there is some setting that needs changed, and I hope someone could point me in the right direction.

 

I'd just suggest checking the manual for that motherboard. It is rather old so there is a chance it just doesn't take 256MB sticks. It's max size per stick could very well be 128MB per stick.

 

I'ts 256 MB PC133. According to Gigabyte and Crucial, the mobo supports it. It will clock down, but that shouldn't cause it to be recognized as 128 MB, should it? Maybe I should trade it in for PC100 memory.

 

My best guess is since it only takes up to PC100 it's causing problems. Although I really don't have a lot of experience with putting better RAM into older motherboards, so I'm not exactly sure how it would deal with that.

If it's possible to trade it in for PC100 memory without having to pay more I'd highly suggest it.

 

Last time I saw this it was because the mobo didn't support 256 sticks.

 

It could also be that your motherboard only supports single sided ram chips! I have ran into this issue twice before. The fact that it recognizes it as 128 instead of 256 would seem to support this. Was your orignal 64 meg chip single or double sided?