View Full Version : Memory upgrade slows computer

06-11-2002, 09:13 PM
What would happen if you use non-parity RAM on a parity motherboard?

I upgraded a friend’s pc from 16MB to 128MB of 72pin RAM, but I couldn’t see any improvement in performance. It’s and older Pentium 100 with an Elite Group SI54P AIO motherboard. It was running 95 but now has 98SE.

The POST went fine and both the BIOS and Windows recognize the RAM.

I did run DocMemory and everything passed.

The mobo manual lists a jumper for “DRAM parity check,” but when I found it on the board, there was no jumper, just a soldered connection. (Why would that be?) Thus parity is in the “enabled” mode.

The original 16MB of RAM had four chips and one very small one that I’ve discovered to be a parity chip. The mobo manual says it supports both fast page mode and edo drams.

So, I seem to have installed non-parity RAM on the mobo, but it’s set to parity. I’m just not positive I’ve done it since it passed POST and there were no error messages. The system performance with the “upgrade” seems poor. Would this be symptomatic of the problem?

Also, could someone recommend a place to buy this type of RAM cheap(ish)?



the highlander
06-11-2002, 10:42 PM
I may be misunderstanding your post but :

your friends P100 had 16 meg of ram running win 95 and you see no performance difference running win98 se on 128 meg of ram

That would be reasonably consistent from what I've experienced with many upgrades of ram and o/s (on everyday mundane tasks).
Win 98 sucks alot more resources than win 95 and a p100 is marginal at best no matter how much ram you stuff into it.

and before I get shouted down I have installed win 98 on a 486 dx66 with 8 megs of ram and it works but its like shaving your legs with a cheese grater slow, painful and ineffecient.

07-11-2002, 05:19 AM
yes, that's what has happened. the os was upgraded first and 98se seemed to work fine, that is, no slower than 95.

the main thing i want to know is if the reason i don't notice any improvement is because of installing non-parity ram on a mobo set for parity. will i see the performance increase with the proper ram, or is the current processor and OS going to hold me back? i always thought that a RAM upgrade, especially a large one from 16mb -128mb, would be very noticeable.


07-11-2002, 06:53 AM
Part of the problem may lay with the motherboard chipset. Some of the earlier chipsets would only cache a maximumof 64MB of ram, so increasing ram above 64MB results in a performance degrade (which will offset the gain made by the increased ram).

If you have 4 x 32MB sticks installed, try removing 2 of them, to reduce the memory to 64M - you might find the performance better than with 128M. The performance difference between 16M and 64M should be noticeable, but cetainly not outstanding. :(

07-11-2002, 09:26 AM
I had a P75 running 64MB RAM, anything above that, and you're right, it did slow. I'm surprised you managed to find EDO RAM so long after its become un-popular. I priced it up from DSE and 128MB would cost about $400, Id rather buy a new motherboard and stuff!!!

wuppo's advice was good, also, try opening winamp (If you have it coz it'd use most of that ram on a p100) and also a few browser windows (Pref IE). see if it has made any difference to before the upgrade.

Somebody once told me that EDO RAM needs to be filled up before it is recognised and fully usable. I dont think that's true though.

But multi-tasking should be a bit better. the proccessor would be your bottle-neck now.

Terry Porritt
07-11-2002, 11:00 AM
Despite what the manual says, perhaps your m/b doesnt support parity checking, in which case it may not matter whether you do use parity chips or not. It was usual to disable parity checking if parity and non parity chips were used together. If no error messages are thrown up I wouldnt worry too much, but Im a bit rusty on this topic.

If you're happy with a soldering iron you could snip through the solder bridge, and if anything untoward occurs, then re-solder.

The CMOS set up could be checked to see if there is a parity setting in there. You could also play around with timing and wait-state settings until you get the best performance. EDO will be better if you can get it, both FP and EDO are getting harder to get, and it can be pricy from a dealer.

07-11-2002, 01:40 PM
Best place I know of for older ram is ComputerBroker (http://www.computerbroker.co.nz).
$140 for 2 x 32Mb sticks, used

07-11-2002, 02:23 PM
I had two, but sold them to my boss, made about a hundred bucks off it. if you ask me, you're better off going for a whole M/Board upgrade. it'll cost you about $260 all up if you're in auckland, that's a M/Board with sound, LAN, onboard VGA, but no modem. Duron 900Mhz already placed on it for you, with Heatsink. and then from DSE - 128MB RAM fro about $40!

Cheap, and a whole lot faster too!!!!

07-11-2002, 02:57 PM
Don't forget you're probably looking at needing an ATX case/power supply as well, if you want to 'upgrade'

Graham L
07-11-2002, 04:37 PM
I am guessing that the soldered jumper is disabling the parity check. Or the manufacturer is telling lies. If you insert non-parity memory in a parity-tested system, you will get frequent error messages. Or you have very strange data and programmes, where all bytes have an odd number of set bits. :D

It has been known for manufacturers to tell lies. There are "parity simms" which dont have parity RAM; they have a parity calculator chip to always return the "correct" parity bit. I am sure that there are motherboards which have dummy parity checking chips. (Remember the cache chips which weren't?).

Some types of memory have needed to be installed in pairs, so that they could be interleaved for full speed.

07-11-2002, 07:16 PM
Thanks for all the input.

wuppo: the chipset is a SiS 5501/5502. does that mean anything to you?

terry porritt: i checked cmos and there are no settings i found to change parity. it only provided a jumper which i mentioned had been soldered.

many of you mentioned upgrading the mobo. trust me, i've raised this topic as well, but he'd rather save the cash. incidentally, i picked up the edo ram in the states for US$7 per 32mb simm. so this would be a cost effective upgrade for someone who doesn't do much on his pc (which my friend doesn't!).

so, what i'm hearing is ditch the 128mb and go with 64mb and i'll be better off. i shouldn't bother trying parity simms since it wouldn't make any difference. is this correct?