Pogromist_su wrote on 2025-04-29, 08:46:No problem! […]
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dionb wrote on 2025-04-25, 10:10:
I can't quite read the inscriptions on the chips on the DIMMs. Could you please give the model numbers of the chips on each DIMM? I can't make them out clearly on the photograph.
No problem!
These chips are working:
- 0029PR
V54C365804VCT7
(IBM FRU 19K3293 64MB DIMM/MOSEL VITELIC PC133U)
OK, these are 8Mx8 8-bit wide 64Mb chips, assumedly 8 on the (single-sided) DIMM to make 64MB total. These are fully expected to work, so prove that the motherboard itself if good.
These chips are not: […]
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These chips are not:
- hynix 619U/622U
HY57V561620CT-H
KOR
(Memory Power 256MB PC133)
These are 16Mx16 16 bit wide 256Mb chips, assumedly 8 on the (electrically double-sided, even if chips are only on one side) DIMM to make 256MB total. Officially the i810 only supports up to 128Mb chips, but if that were the only problem, these DIMMs would work at half capacity, i.e. as 128MB DIMMs, they would not fail completely.
- MALAYSIA
81117822A-100FN
9747-F64
(HP DIMM SDRAM 9ns 4Mx64)
Despite Fujitsu being a major chip vendor, I'm having trouble finding a datasheet for 81117822A-100FN. However attempting to decode the chip name myself, it looks like this is a 2Mx8 8 bit wide 16Mb chip. If that's the case, this is either a 16MB single-sided (if there are 8 chips on it) or 32MB double-sided DIMM (if 16 chips). Aside from the small size, these chips support 2k refresh instead of the later more common 4k refresh. This could explain why they don't work on the board.
These are very weird chips - BGA packages were pretty unheard-of for SDR-SDRAM. Whoever made them it's not "WIN". However the chip structure is clear enough: 8Mx16, i.e. 16 bit wide 128Mb chips. Which is odd for 256MB, as a DIMM can normally only support one bank (64b wide) or two banks (128b wide). 8 of these chips would give 2 banks but only 128MB. If there are 16 of these on the DIMM (needed to make 256MB), that would make four banks on a single DIMM, which is wildly out of spec and basically impossible in a 168p DIMM. So either this is not a 256MB DIMM or the "8Mx16" on the chips is not correct.
Based on this, I would expect:
- Memory Power 256MB PC133 would work, but only as 128MB
- HP DIMM SDRAM 9ns 4Mx64 would probably not work, and even if it did this is max 32MB in size
- no idea with the "WIN 8MX16FF"
If you want 256MB modules that are certain to work at full capacity on i810, you need modules with 16 128Mb chips with 16Mx8 layout.
Double-check:
- are these known-good DIMMs? (i.e. do the work in other systems?)
- if so, what memory controller (chipset) does that system have?
- if so, what size do they report there?
