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SPD Chip Programming

trag

Well-known member
Any Mac hacks out there to let one program the SPD chip on a DIMM?

I know such things exist in the Windows world.

 

khmann

Member
DIMM First Aid does something... I think it copies the profile from working sticks to non-working ones. I too would like a better solution then keeping a collection of PC desktop and laptops just to run SPDTool...

 

trag

Well-known member
Thank you. I'll look into that.

So, will a machine boot with one good DIMM and one unrecognized DIMM? For example, an MDD?

I think, ultimately, I'll probably have to just pull the SPD chip and program it with a chip programmer. Sigh.

 

khmann

Member
Hmm... Not sure about that. I have in the past (many times) "hot plugged" a stick with bad SPD, while the machine is idle at open firmware or boot menu, but that is a TERRIBLE idea and you should not do it... Working on under warranty hardware and with essentially unlimited replacement parts sometimes makes one take stupid risks... Though fwiw, I have never had a problem.

also I never tried DFA with a DDR Mac... MDD do seem very particular about SPD though, it took me three tries to get a profile which would not intermittently freeze my machine (and I really don't know what was different... It wasn't something obvious like CAS latency or speed...)

Rather than desolder EEPROM, it would probably be easier just to solder 3 or 4 small jumper wires or hack up an old slot to make an adaptor.

 

techknight

Well-known member
alot of PC DDR1 and SDRAM laptops were VERY picky about the SPD chips, such as compaqs, and dells. I had a compaq that took DDR PC2100/266 and would NOT take anything else BUT that.

(sorry, not mac related)

 
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