P4 Computer problems

[Airhog]

My GF's dad bought her a motherboard and processor. Its a P4 processor. The motherboard uses rambus memory. Originally he just tried to install 1 memory stick and leave one slot open. I read up on rambus since I havent used pentiums since the p2, and found out that they have to be installed in pairs. So he gets another dummy board thinking he can install just one chip and 3 dummy sticks. However, the fan still refuses to spin up on the motherboard. Do you need a minimum of 2 rambus chips for it to work? Should the be the same size and speed or can you mix and match. normally i would just google for the info, but I see conflicting information.

[Draft Dodger]

try just the 1 chip and 1 dummy - I think it could be the other 2 dummy sticks that is throwing it off.

[Airhog]

no it says that all 4 slots must be populated with memory or dummies, however i found some stuff on intel that leads me to believe that you must use pairs of memory on both banks. The pairs must be the same size, however the banks do not have to be the same size.

[Draft Dodger]

Originally posted by Airhog
no it says that all 4 slots must be populated with memory or dummies, however i found some stuff on intel that leads me to believe that you must use pairs of memory on both banks. The pairs must be the same size, however the banks do not have to be the same size.

I'm not that familiar with rambus, but that doesn't seem very intuitive to me. I'm pretty sure I'd seen some rambus p4's that shipped with 1 chip and a dummy, and the other 2 banks empty. maybe it's a specific of the mobo? maybe you need to shut off that 2nd bank somehow in the BIOS? also - you sure it's not a different issue with the computer?

(the second part makes sense - pairs the same, but the two banks don't need to match)

[Airhog]

well its takes two-channel rambus. It also says in the manual that it must be installed in pairs, but it makes no mention of if a dummy will work instead.


It very well could be an issue with the motherboard or the processor.

[Airhog]

I finally tracked down the company that made the mb, and sent them some questions. thanks for the help :)

[Draft Dodger]

interested to see how it turns out.

[HeavyReign]

In most cases I would expect the power to come on and then give you some sort of beep code if there is a problem with the RAM. The first thing I would check is the connection to the power supply.

[Airhog]

HeavyReign: you would think so. But I checked out a board that intel makes that uses Rambus. It stated that the mb wouldnt run post and give any error codes if the memory was installed properly. I know the power supply is good, because we have 3 other old mb's that spun up when we connected them to the power supply. However, the p2 wouldnt spin up until we added memory.

[HeavyReign]

What motherboard is it? I know some of the newer boards have a second power connector on the board and an older power supply might not have the extra connector.

[Airhog]

no, this is an ATX board in an ATX case, with an ATX power adapter. The other boards we tested were all ATX as well. Also we tried 2 other power supplies that were brand new out of the box, and it didnt spin up.

[dacman]

When the Rambus boards first came out, it was a requirement to add the ram in matching pairs, so I suspect your board may not be new enough to handle a dummy.

[Sloan]

Most Rambus boards have 2 memory channels with 4 memory slots on the board. You need to fill both slots of one channel with matching memory. The other two slots can be dummy sticks (CRIMMS) or two other matching memory sticks.

Most boards need slots 1+2 to match and 3+4 to match. I have seen some boards that stagger the memory channels so that slots 1+3 would need mathching memory and slots 2+4 could have the dummy sticks or memory.

[Airhog]

Sloan: thanks. I had read that exact same thing on intels site, but i wasnt sure if it was specific to just their mb, or for all of the older boards.

I assume this board is old since you can buy one for 11 bucks on the internet :D

[Sloan]

Originally posted by Airhog
Sloan: thanks. I had read that exact same thing on intels site, but i wasnt sure if it was specific to just their mb, or for all of the older boards.

I assume this board is old since you can buy one for 11 bucks on the internet :D

Yeah that sounds like an old one. :D

With a board that old, you might run in to compatibility problems with new RAMBUS memory. If the board requires PC800 memory newer PC1066 memory may not work very well. In theory it should, but I know my P4 board didn't like newer memory. I had to track down some old stuff to upgrade my PC.

[Airhog]

yeah this board is made for pc800 memory. I will keep that in mind.

[Gallifrey]

I am sure this is an old issue...

Rambus must be in pairs as you know, and you can do it in pairs of 1 800mhz clip and 1 continuity clip and so on.
You don't have to match the RAMBUS to the motherboards bus speed, but it is advised.
For instance..if you have an Intel 800GB Motherboard, which has a front side bus of 400mhz, you will only get a max of 400mhz from the RAMBUS.
The P4 will want all it can get, so the idea is to max your bus to clock it out.

Your motherboard should not require all slots to be filled, only two of the four I assume it has.