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jhuffman

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Parity error

My 60 mhz computer came with 16 mb RAM. The manual says to use parity memory only.  When I removed two 4 mb SIMM's and put in two 32 mb SIMM's 72 mb were "tested" at bootup, but Only 64 mb were available for use. When I change the set-up to test parity, I get parity error at 0000-0002.
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johncook

If these are not the 72 pin type SIMMs you need to install 4 at a time NOT two.
An judging by the fact that this is a 60Mhz board they are probably 30 pin SIMMs. So..you will need 4 32 M simms to achieve your desired result.

If I've misread let me know.

John C. Cook

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ASKER

The motherboard is a "SUPER P5VESA", it definately uses 72 pin SIMMS.  It requires the parity bit. Does thid help?
Does parity setting work okay when using the original memory?
Try substituting the original SIMMS with the new ones.
How much RAM is then indicated at bootup?
Regards,
Ralph

The SUPER P5VESA was manufactured by SUPERMICRO around 1994 so it is dated a little. This board my not support more than 64Meg of Ram. hmmm, except that you say 72M is tested at bootup...do you mean before DOS boots when the CMOS memory check is performed?
I am searching to see if I can verify this as a fact..anyone?

You could try changing some CMOS settings which relate to ram speed...i.e. go with safe settings instead of the optimal.. These are usually settable from the CMOS.



John C. Cook
No i was wrong it should support up to 128 M fast page ram.
Is this the same MB as you have?

SUPER P5VL Specifications

PROCESSOR
Pentium processor 66/60 MHz
128/256/512 KB WB or WT cache

CHIPSET
Opti 82C597/82C596/82C822 PCIset

EXPANSION
4 32-bit PCI slots
2 32-bit VL slot
5 16-bit ISA slots

SYSTEM MEMORY
4/8/16/32 MB fast page mode
4 72-pin SIMM sockets support up to 128 MB

BIOS
AMI Flash WinBIOS
Power saving function
Adaptec 7850 and NCR 810 support
Plug and Play support

jhuffman,
We need some feedback from you.
Ralph

First check you first 2 4MB simm does it have parity chip on it.
If it don't have parity chip on it, your system board will not see the last 2 4MB Ram.  I think your original setting in you CMOS, the parity check is disable.  If you take out last 2 4MB ram and put the 2 new 32MB SIMM on the system board, and enable the parity check in CMOS, you system will run.
You can also do an other way is just disable parity check in you CMOS, I think that will give you 72MB on the system.
 
Let me know how it works, see you later JHUFFMAN
Gentlemen
This is my first experience with experts-exchange, so I am weak on protocol.

My system does not quite match johncook's comment.  It has:
Opti 82C597/82C596/82C206 chipset. Integrated Peripherals Contoller (IPC).

With 4 mb SIMM's in banks 0 and 1 I can boot up with parity check enabled.  The fulll memory is tested and shown in MEM report.

With 32 mb SIMM's in banks 0 and 1 boot up with parity enabled results in fatal parity error message.  Without parity check the full 65152 kb is tested and reported by MEM.  The system runs OK.

With 4 mb in 0 and 1, and with 32 mb in 2 and 3, boot up tests 72 mb but MEM reports 64 mb. (with partity check disabled)

I have purchased two more 32 mb SIMM's (with parity bit)
With 32 mb SIMM's in all 4 slots 128 mb is tested but MEM reports 64. (with parity disabled).

I have tried many combinations of configurations.  Neither set of 32 mb SIMM's ever pass parity check.  All installed RAM is tested OK.

My original 4 mb SIMM's are 70 nsec, both sets of 32's are 60 nsec.  Any relavence?



 

How many physical chips are on the 32MB vs the $MB SIMMS?

rmarotta

My 4 mb SIMMs have 9 chips marked:
TI
TMS44400DJ
TBO  4013Y0

My first set of 32's have 16 chips marked:
TOSHIBA H5065Y
9721HAK
TC5117400CSJ-60
PLUS ONE THIN SQUARE CHIP MARKED:
BP44C
8001C-6
9628

My second set of 32's HAVE 16 CHIPS marked:
OKI JAPAN
M511700B-60SJ
81254219A9Z
Although I haven't identified those chip part numbers, I think your 32MB SIMMS are non-parity types.
Parity SIMMS usually will have an odd number of DRAM chips on them.
See the info at this site for more information:
http://www.pcguide.com/ref/ram/pack.htm
Let me know if you need more.
Regards,
Ralph

I quite agree with rmarotta...
3 chip and 9 chip(especially 9 chip indicate parity ram).So it would stand to reason that the higher MB ram chips should follow this same convention.


The MB info I pulled down was from a newer version of the P5vesa board...I was not sure if it would match or not.

Does your MB board book have a RAM matrix..i.e. all the possible combinations of chips possible to achieve specific MB levels? If so, does it show the combination you are trying to use?

John C. Cook
by the way it is OK to reject my answer, since it didn't solve your problem. This will put it back up where more folks will view it and get a chance to help you.

Later,
John C. Cook
From Ralph's comments and info at the pcguide web site he recommended, I feel as certain as I can the 32 mb SIMM's that I bought are not the parity type.  My receipt says 8 X 36, but I will go back to the Computer Show (Swap meet) and try to exchange them for what I paid for.  
I have learned a lot about memory and a lesson regarding buying something that I don't know about at a swap meet.
Hopefully I will get this done and report the resolution Monday.
If you can find the same folks.. you generally will not have any problem exchanging them even at a show..
John C. Cook
I successfully exchanged both sets of 32 mb SIMMs.  Now I can boot up with parity check enabled and all 128 mb is tested with no error notices.  I consider rmarotta's answer acceptable. How do I make the points go to him?
I will start a new question now because I still only have 64 mb when I run MEM.  The Set up screen also shows 64 mb right after testing 128.
If you want to award your points to someone else, you must first select "re-open the question to another expert" from your list of options.
You can then leave a comment asking the expert of your choice to submit his answer for you to grade.
You do not have to accept an answer until your problem is solved to your satisfaction.
Regards,
Ralph

rmarotta-
I guess there can be only one "proposed answer".  I have reopened the question so you can respond.  My memory not really being parity was correct.  I believe I have another separate problem now that I will enter for an answer.

As a matter of interest, today I watched a technician upgrade my computer at work to 128 MB.  After installing the new memory MEM reported 64 mb total with just under 128 mb available!  The new memory was functional.  

My home machine reports 64 mb total and 64 mb available. (with 128 tested).  If this is an easy one I will be happy to add my remaining 65-70 points.
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rmarotta

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