Perhaps I didn't read properly, does the issue also occur if you just idle around in BIOS etc?
Some cards with memory issues that I had in the past worked mostly "okay" until the driver has been loaded.
Regarding mapping your memory to the result of the tool:
You'll need a schematic of a 9550 or 9600, often the memory alignment (data bits to memory chips) is the same even if the rest of the layout is different.
There you'll see which data bit goes to which IC. They often also describe where the memory is located on the board.
The RV350/RV360 have two memory channels, A and B, each 64bits => 4 x 16 Bit ICs if TSOP-66 memory is used like on your card.
Fortunately board partners often just copied big chunks of the reference design, like the memory part. So you'll find the exact same memory arrangement and identifiers even if other parts are different. I attached the schematic of a Radeon 9600 from gigabyte for you. It's not exactly the same in terms of the power section, but memory looks good.