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Top Tip: Computer sees only 50% of new RAM!

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Question from Rod "For the new school year I was upgrading the kid's legacy (read ancient) computer.

It had 1x PC133 SD64MB module in one of 3 banks, I'm trying to add 3x PC133 SD128MB modules (manufactured by Centon).

When 1x SD128MB is in the computer, it sees 64MB of RAM; when x2 128MB it sees 128MB; when x3, 192MB.

The motherboard, with an AMD K6 CPU, is a Chaintech 5SSV with a SiS 530/559 chipset. The motherboard manual says it will accept single/double-sided DRAM in modules of 16/32/64/128MB, either parity or non-parity.

The CMOS/BIOS is, according to the Chaintech homepage, the most recent."

Answer from tachyonpcco "it can probably only see 64MB in each bank, thus you can only have a max of 192MB of memory and only 64MB in each bank, i think the manual is inccorect or probably a typo or can be used with another model motherbaord therefore the manual is probably too general. "

Answer from QuantumLeaper (QUANTUMLEAPE) "I had a simular problem with my old P2 400, I know for a fact it supports 128M, I had 2 out of the 4 banks populated with them, and I got 2 more 128M from Best Buy, they were on sale. The new ones ONLY worked at 64M instead of the 128M that was on the package.

I tried the memory in another computer, and it worked ONCE at 128Megs and when I rebooted it was down to 64Megs again. So I returned the faulty memory and bought a different no name kind, which did work with out a problem."

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