VOGONS


32MB showing up as 8MB

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First post, by Lo-ResBros

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I have a Tyan S1470 motherboard and 32MB SDRAM PC100, but it only shows up as 8MB. Is there anything I can change in bios to allow it to see the full 32MB?

Is it possible that PC100 doesn’t work well this board? I ordered a stick of PC66 to try and hopefully that will solve the problem. Any suggestions appreciated!

AMD K6-2+/550MHz
Soltek SL-54U5 Super Socket 7
64MB SDRAM
3DFX Voodoo 3 3000 16MB
Sound Blaster AWE64
Roland SC-55mkII

Pentium MMX 233MHz
Tyan TitanVX S1470 Socket 7
128MB SDRAM
ATi Rage 128 pro 32MB
Audio Plus 320 v.1
Roland SC-88

Reply 1 of 28, by Tiido

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Pentium1 chipsets are very picky with the SDRAM sticks, amount of chips and their density matters. I'm not sure what exactly these chipsets expect, I try random sticks from my stash until I find a combination that works.

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Reply 2 of 28, by Lo-ResBros

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Tiido wrote:

Pentium1 chipsets are very picky with the SDRAM sticks, amount of chips and their density matters. I'm not sure what exactly these chipsets expect, I try random sticks from my stash until I find a combination that works.

Thanks I had a feeling it just didn't like these sticks, ordered a couple different options to try!

AMD K6-2+/550MHz
Soltek SL-54U5 Super Socket 7
64MB SDRAM
3DFX Voodoo 3 3000 16MB
Sound Blaster AWE64
Roland SC-55mkII

Pentium MMX 233MHz
Tyan TitanVX S1470 Socket 7
128MB SDRAM
ATi Rage 128 pro 32MB
Audio Plus 320 v.1
Roland SC-88

Reply 4 of 28, by dionb

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All this talk of "low density" and stuff like that are the reason that people treat this like unknowable mumbo-jumbo...

Any chip density will be "high density" when introduced and "low density" a few years later, so they're useless terms, particularly in retrospect. It's not that difficult.

The i430VX memory controller supports max 16Mb chips, giving you 16MB on a single-sided module and 32MB on a double-sided module with 16 chips. Not much, but fits their caching abilities - max 64MB. On the i430TX those two were definitely not in sync - officially it supported up to 64Mb chips, in practice it was able to handle 128Mb chips, so you could feed it 256MB dual-sided DIMMs for a grand total of 512MB. But it could still only cache 64MB...

Reply 5 of 28, by Lo-ResBros

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BastlerMike wrote:

430VX Chipsets Supports only 32 MB low density SDRAM. Make sure your memory stick has 16 pieces of memory chips. Modules with less memory chips will not be recognized properly.

fortunately one of the sticks I bought today on ebay has 16 chips on the stick... so hopefully that will workout!

AMD K6-2+/550MHz
Soltek SL-54U5 Super Socket 7
64MB SDRAM
3DFX Voodoo 3 3000 16MB
Sound Blaster AWE64
Roland SC-55mkII

Pentium MMX 233MHz
Tyan TitanVX S1470 Socket 7
128MB SDRAM
ATi Rage 128 pro 32MB
Audio Plus 320 v.1
Roland SC-88

Reply 6 of 28, by Lo-ResBros

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dionb wrote:

All this talk of "low density" and stuff like that are the reason that people treat this like unknowable mumbo-jumbo...

Any chip density will be "high density" when introduced and "low density" a few years later, so they're useless terms, particularly in retrospect. It's not that difficult.

The i430VX memory controller supports max 16Mb chips, giving you 16MB on a single-sided module and 32MB on a double-sided module with 16 chips. Not much, but fits their caching abilities - max 64MB. On the i430TX those two were definitely not in sync - officially it supported up to 64Mb chips, in practice it was able to handle 128Mb chips, so you could feed it 256MB dual-sided DIMMs for a grand total of 512MB. But it could still only cache 64MB...

the 32MB stick I was trying to use is single sided and only has 4 chips on it. 4MX64

so from what I read in your post, this chip definately wouldn’t work properly with this board. Thanks for the clarification and info

AMD K6-2+/550MHz
Soltek SL-54U5 Super Socket 7
64MB SDRAM
3DFX Voodoo 3 3000 16MB
Sound Blaster AWE64
Roland SC-55mkII

Pentium MMX 233MHz
Tyan TitanVX S1470 Socket 7
128MB SDRAM
ATi Rage 128 pro 32MB
Audio Plus 320 v.1
Roland SC-88

Reply 7 of 28, by dionb

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Lo-ResBros wrote:

the 32MB stick I was trying to use is single sided and only has 4 chips on it. 4MX64

so from what I read in your post, this chip definately wouldn’t work properly with this board. Thanks for the clarification and info

32MB with 4 chips means that they are 64Mb chips, so no, they would only get detected as 1/4 of their stated capacity with a memory controller only capable of handling 16Mb, which is exactly what you are seeing.

That "4MX64" doesn't actually tell you very much, as the 64 there is referring to the 64 bit-wide data path of the DIMM, so it's not actually telling you anything about the structure of the chips on it.

Reply 8 of 28, by Lo-ResBros

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dionb wrote:
Lo-ResBros wrote:

the 32MB stick I was trying to use is single sided and only has 4 chips on it. 4MX64

so from what I read in your post, this chip definately wouldn’t work properly with this board. Thanks for the clarification and info

32MB with 4 chips means that they are 64Mb chips, so no, they would only get detected as 1/4 of their stated capacity with a memory controller only capable of handling 16Mb, which is exactly what you are seeing.

That "4MX64" doesn't actually tell you very much, as the 64 there is referring to the 64 bit-wide data path of the DIMM, so it's not actually telling you anything about the structure of the chips on it.

ok I think I get it now 🤣

I bought a 128MB stick PC66 since it was cheap and thought it might work, but since it has 16 chips and is a 128MB stick, then I’m guessing the 16 chips are 64MB so while it might work, it will only detect 1/4 of it and I’ll be left with 32MB. the chips on the stick say “MT48LC8MA2TG” on them which I looked up are 8 meg x 8 (64).

I’ll have to look harder for some better sticks but thanks to you guys I have a better idea what to look for

AMD K6-2+/550MHz
Soltek SL-54U5 Super Socket 7
64MB SDRAM
3DFX Voodoo 3 3000 16MB
Sound Blaster AWE64
Roland SC-55mkII

Pentium MMX 233MHz
Tyan TitanVX S1470 Socket 7
128MB SDRAM
ATi Rage 128 pro 32MB
Audio Plus 320 v.1
Roland SC-88

Reply 9 of 28, by The Serpent Rider

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I think I've managed to boot at full 64mb SDRAM capacity with single sided module (1 rank) with late revision of Asus P/I-P55TVP4 (two DIMM slots). Will investigate later.

I must be some kind of standard: the anonymous gangbanger of the 21st century.

Reply 10 of 28, by Tetrium

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Lo-ResBros wrote:
ok I think I get it now lol […]
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dionb wrote:
Lo-ResBros wrote:

the 32MB stick I was trying to use is single sided and only has 4 chips on it. 4MX64

so from what I read in your post, this chip definately wouldn’t work properly with this board. Thanks for the clarification and info

32MB with 4 chips means that they are 64Mb chips, so no, they would only get detected as 1/4 of their stated capacity with a memory controller only capable of handling 16Mb, which is exactly what you are seeing.

That "4MX64" doesn't actually tell you very much, as the 64 there is referring to the 64 bit-wide data path of the DIMM, so it's not actually telling you anything about the structure of the chips on it.

ok I think I get it now 🤣

I bought a 128MB stick PC66 since it was cheap and thought it might work, but since it has 16 chips and is a 128MB stick, then I’m guessing the 16 chips are 64MB so while it might work, it will only detect 1/4 of it and I’ll be left with 32MB. the chips on the stick say “MT48LC8MA2TG” on them which I looked up are 8 meg x 8 (64).

I’ll have to look harder for some better sticks but thanks to you guys I have a better idea what to look for

As long as you get 32MB SDRAM with 16 chips (so 8 each side), you should be fine provided the modules work proberly. These modules had chips that were a bit shorter compared to the chips that have 4x the density (or the size, or however you want to compare it) and the vast majority will be PC-66.
PC-66 SDRAM that has the higher density chips were a lot less common, and I see them as not very useful as most of the memory won't be seen properly in most P1 boards and P2 and SS7 boards work fine with higher binned memory chips of greater speed (so PC-100 and up).

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Reply 11 of 28, by dionb

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Lo-ResBros wrote:

ok I think I get it now 🤣

I bought a 128MB stick PC66 since it was cheap and thought it might work, but since it has 16 chips and is a 128MB stick, then I’m guessing the 16 chips are 64MB so while it might work, it will only detect 1/4 of it and I’ll be left with 32MB. the chips on the stick say “MT48LC8MA2TG” on them which I looked up are 8 meg x 8 (64).

I’ll have to look harder for some better sticks but thanks to you guys I have a better idea what to look for

You're mixing up your capitalization, i.e. your bits and Bytes - that's a surefire way to get confused.

1B=8b, DIMM sizes are measured in (kilo/Mega/Giga)Bytes, but chip densities (=size) are mesured in (kilo/Mega/Giga)bits.

128MByte with 16 chips has 8MByte chips (128/16=8). 8MByte=64Mbit (8x8=64). So yes, if your RAM controller can handle max 8Mbit, it will register as 32MByte.

In this case the specs are useful, 8Mx8 tells you both the chip width (8 bits) and the density (8x8=64Mbits). One bank is 64b wide, so on a DIMM you need 8 of these for a single bank ("single-sided" DIMM) or 16 for two banks ("double-sided"). Note that those terms are slightly misleading - it's entirely possible to have a single-sided DIMM with chips on both sides, just as you can have double-sided DIMMs with chips on only a single side.

If you get into the habit of being consistent and accurate with b&B, it all falls into place.

Reply 12 of 28, by Kcil

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Hi, I have seen this topic being asked quite frequently. One thing I hope someone can shed a light, given that 128MB SDRAM with 64Mb chips are much easier to find and cheaper than 32MB SDRAM with 8Mbit chips (at least in my area), is there any downside in using 128MB SDRAM in my P1 rig where it is detected as 32MB only? The board is 430VX.

Is there any problem with the fact that the chipset only caches 64MB of RAM? Not sure how it is being handled physically in the system.

Reply 13 of 28, by dionb

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No downside to using a larger DIMM that is only partly being addressed. It's a "waste", but if it's easier to source the larger module, that's not really an issue.

As for caching, that only happens over the addressed area (it's one layer up, logically speaking), so only the memory actually detected counts. As far as an i430VX motherboard is concerned, that 128MB DIMM with 64Mb chips is a 32MB DIMM with 16Mb chips and so all those 32MB can be cached (as indeed could a second identical DIMM).

Reply 14 of 28, by Kcil

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dionb wrote:

No downside to using a larger DIMM that is only partly being addressed. It's a "waste", but if it's easier to source the larger module, that's not really an issue.

As for caching, that only happens over the addressed area (it's one layer up, logically speaking), so only the memory actually detected counts. As far as an i430VX motherboard is concerned, that 128MB DIMM with 64Mb chips is a 32MB DIMM with 16Mb chips and so all those 32MB can be cached (as indeed could a second identical DIMM).

Nice! Thanks a lot, you've been most helpful.

Reply 15 of 28, by amadeus777999

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I also have a few boards that only "permit" 32MB sticks.
A bit impractical... "mebi" try to get 16 chips modules.
Shouldn't the units based on powers of 2 be called KiB, MiB, etc?

Reply 18 of 28, by Kcil

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dionb wrote:

No downside to using a larger DIMM that is only partly being addressed. It's a "waste", but if it's easier to source the larger module, that's not really an issue.

As for caching, that only happens over the addressed area (it's one layer up, logically speaking), so only the memory actually detected counts. As far as an i430VX motherboard is concerned, that 128MB DIMM with 64Mb chips is a 32MB DIMM with 16Mb chips and so all those 32MB can be cached (as indeed could a second identical DIMM).

Hi, just found a conflicting fact. I tried to install 2 sticks of 128MB SDRAM with 16 chips, and my computer POSTed with memory test failure. I have isolated the problem that my board simply wont accept 2 sticks put together (I have placed each stick in each DIMM and in all cases, my computer will POST successfully).

Then I put in a 256MB SDRAM stick with 16 chips (if I calculate correctly that means each chip is a 128Mb chip) and the BIOS reported 64MB of RAM. Checked the integrity with Memtest and it passed 100% test. Wouldnt this mean 430VX can make do with 32Mb chip (16x 32Mb = 64MB, right?) So this contradicts with the info you said that VX can only see 16Mb per chip. Or is there a mechanism where physically the memory stick has 16 chips, but the system sees 32 chips instead?

I have quickly tested with another 430vx board and the result is the same (BIOS sees 64MB of RAM).

Reply 19 of 28, by Tetrium

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Kcil wrote:
Hi, just found a conflicting fact. I tried to install 2 sticks of 128MB SDRAM with 16 chips, and my computer POSTed with memory […]
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dionb wrote:

No downside to using a larger DIMM that is only partly being addressed. It's a "waste", but if it's easier to source the larger module, that's not really an issue.

As for caching, that only happens over the addressed area (it's one layer up, logically speaking), so only the memory actually detected counts. As far as an i430VX motherboard is concerned, that 128MB DIMM with 64Mb chips is a 32MB DIMM with 16Mb chips and so all those 32MB can be cached (as indeed could a second identical DIMM).

Hi, just found a conflicting fact. I tried to install 2 sticks of 128MB SDRAM with 16 chips, and my computer POSTed with memory test failure. I have isolated the problem that my board simply wont accept 2 sticks put together (I have placed each stick in each DIMM and in all cases, my computer will POST successfully).

Then I put in a 256MB SDRAM stick with 16 chips (if I calculate correctly that means each chip is a 128Mb chip) and the BIOS reported 64MB of RAM. Checked the integrity with Memtest and it passed 100% test. Wouldnt this mean 430VX can make do with 32Mb chip (16x 32Mb = 64MB, right?) So this contradicts with the info you said that VX can only see 16Mb per chip. Or is there a mechanism where physically the memory stick has 16 chips, but the system sees 32 chips instead?

I have quickly tested with another 430vx board and the result is the same (BIOS sees 64MB of RAM).

I wasn't expecting this, but it wouldn't be impossible for a "discovery" like this to be made (this forum is full of discoveries 😁).
For instance, 440LX was reported to work only with 128MB SDRAM modules, but it will work with 256MB SDRAM modules (both LX and BX have the same limitations though regarding certain higher density memory modules).

But it may be some odd thing to do with your memory module or it may be your BIOS misreporting or something else.

And even if it were to be legit, it won't guarantee the VX will run stably.

Could you post a couple pics of the memory module and the model numbers of your module and the VX motherboards you are using?

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