ram prob

[bigfella]

hi ,i have a very old computer in the spare room .doin nothing,thought i d upgrade the ram and maybe use it as a spareor let some one have who s want to learn.... it s about 8 yr....runs on xp...it s exceedingly slow..so checked ram and it said 256 so checked on crucial website and ran a scan and it said it was poss to up grade ram to 512 (?) so got the details and bought two lots of 256 and installed into the computer...but it s only sayin 256 of ram instead of the 512 i put it into it ...one thing i did notice was when i took the old out it said pc 100 while the new ram was pc 133...so i m no further forward .. still slo to the point of bein u/s....i wondered if any one out there cud help???? many thanks in advance

[cgscott]

The ram has to be the same speed on old motherboards.

Paired 100 or 133

[bigfella]

The ram has to be the same speed on old motherboards.

Paired 100 or 133

many thanks for your speedy reply
both the old ones i took out where 100 so the two new increased ones need to be 100 too not 133? how cum it workin then ? admittingly only one of the pair seems to be workin tho ........ both new pair are both 133

[cgscott]

If the 2 new ones are 256mb 133 they should run together total 512mb. It doesnt matter what speed they are as long as they are the same.

Sound to me like you have bought some dud memory modules if you only get 256mb yet you install 512mb.

You cant run a 100 and a 133 together on old boards.

On newer motherboards you can run different speed ram although it will only run at the slowest bus speed of one of the memory modules.

[chroma]

Sometimes you can run two sticks that are different, its best to get both 133 here but if one is 100 and the other is 133 you can force them to both work by configuring the memory speeds in the bios.

All memory has a chip config chip on it, the bios configures your speeds normaly by using this SPD chip (serial presence detect) if both config chips differ old computers get confused and rather than just configuring both to run at the lowest speeds supported it will disable one or the other.

To fix it, go into your bios and manualy configure your memory settings to THE LOWEST SUPPORTED STICK this will override SPD and allow both sticks to run more often than not

Just remember to set up the correct voltages and bus timings or you can fry your sticks.

[cunny]

Sometimes you can run two sticks that are different, its best to get both 133 here but if one is 100 and the other is 133 you can force them to both work by configuring the memory speeds in the bios.

All memory has a chip config chip on it, the bios configures your speeds normaly by using this SPD chip (serial presence detect) if both config chips differ old computers get confused and rather than just configuring both to run at the lowest speeds supported it will disable one or the other.

To fix it, go into your bios and manualy configure your memory settings to THE LOWEST SUPPORTED STICK this will override SPD and allow both sticks to run more often than not

Just remember to set up the correct voltages and bus timings or you can fry your sticks.

I thought this was poss but was not 100% Was sure i did it with an old gateway pc on a P1 setup i used to have.

Thanks for jogging the memory cells here chroma

[bigfella]

Sometimes you can run two sticks that are different, its best to get both 133 here but if one is 100 and the other is 133 you can force them to both work by configuring the memory speeds in the bios.

All memory has a chip config chip on it, the bios configures your speeds normaly by using this SPD chip (serial presence detect) if both config chips differ old computers get confused and rather than just configuring both to run at the lowest speeds supported it will disable one or the other.

To fix it, go into your bios and manualy configure your memory settings to THE LOWEST SUPPORTED STICK this will override SPD and allow both sticks to run more often than not

Just remember to set up the correct voltages and bus timings or you can fry your sticks.

cheers for your reply but i switched the ram boards and took them out takin turn s to see which one worked and to see if a slot was faulty ....by doin this i found out one of the new 256 ram was faulty ....i have e mailed the supplier and have asked for a replacement ...hopefully this will solve the problem ...again cheers for ur help,much appreciated

[thanassis]

my friend first of all check what ram you need!!! ( SDRAM?? DDR 1?? DDR 2???)
also there are some types like SIMM or RIMM on old machines!!!
if you tell us which motherboard you have, we can tell you which ram could work!!

pc 100 and 133 are sdram but you should know that the pc133 you will buy, will have back compatibility (to pc100)

also some motherboard could not read more than 384MB or 768MB and you can find it in motherboard manual!!!