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memory bus speeds don't agree
- Thread starter Tybee
- Start date
Some motherboards let you run the processor and memory at different speeds. The settings are in the BIOS. Check your manual.
Just because you installed PC133 memory doesn't mean it will run at 133MHz. It will run at the speed of your Front Side Bus. In your case that's 100MHz.
Hope this helps. Good luck.
John
Just because you installed PC133 memory doesn't mean it will run at 133MHz. It will run at the speed of your Front Side Bus. In your case that's 100MHz.
Hope this helps. Good luck.
John
- Thread starter
- #3
John, Thanks for your advice. I did look up the specs on the mobo, ASUS A7V133 and it will support the PC133 memory but I don't understand the then reference to 266/200 FSB as it relates to memory. Can I use the capabilities of the PC133 with this board? Just how do I change the BIOS?
Enter BIOS setup.
Go to Advanced.
Set DRAM Frequency to 133MHz.
Save the settings and exit.
Then your memory will run at 133MHz.
How does the 200/266MHz FSB work?
I don't know. AMD and other chip makers license this technology from Digital Equipment Corp. and how it works is a well kept secret.
If anyone knows, I would be glad to learn.
All you need to know is that all of the curcuitry doesn't need to work at the same speed. Example: A 1000MHz processor works with a 200/266MHz FSB and 133MHz SDRAM. The inner workings are handled by the processor's Bus Interface Controller and the chipset.
DDR (Double Data Rate) effectively doubles the speed of memory so, in effect, PC-1600 runs at 200MHz and PC-2100 runs at 266MHz.
Hope this helps. Good luck.
John
Go to Advanced.
Set DRAM Frequency to 133MHz.
Save the settings and exit.
Then your memory will run at 133MHz.
How does the 200/266MHz FSB work?
I don't know. AMD and other chip makers license this technology from Digital Equipment Corp. and how it works is a well kept secret.
If anyone knows, I would be glad to learn.
All you need to know is that all of the curcuitry doesn't need to work at the same speed. Example: A 1000MHz processor works with a 200/266MHz FSB and 133MHz SDRAM. The inner workings are handled by the processor's Bus Interface Controller and the chipset.
DDR (Double Data Rate) effectively doubles the speed of memory so, in effect, PC-1600 runs at 200MHz and PC-2100 runs at 266MHz.
Hope this helps. Good luck.
John
Is there a program to diagnose what is the speed of the SDRAM(etc. PC100 or PC133) ? What will happen if putting a PC133 SDRAM on the motherboard which only support PC100 ? Or putting a processor which the speed is higher than the motherboard can support. Will it hang the PC ? Thank you.
Usually PC133 memory will work in place of PC100 memory, unless your motherboard manual says otherwise, it will just run at 100MHz.
Installing an unsupported processor could cause damage to the processor or cause the system not to boot.
Check with the motherboard manufacturer for a BIOS update that supports the new processor.
Some processors use different core voltages, unless your motherboard has an adjustable or automatic VRM (Voltage Regulator Module), they won't work and could be damaged by over voltage.
Hope this helps. Good luck.
John
Installing an unsupported processor could cause damage to the processor or cause the system not to boot.
Check with the motherboard manufacturer for a BIOS update that supports the new processor.
Some processors use different core voltages, unless your motherboard has an adjustable or automatic VRM (Voltage Regulator Module), they won't work and could be damaged by over voltage.
Hope this helps. Good luck.
John
Hi,
this German PC web site has a nifty utility called ctspd that reads the SPD chip off your SDRAM module and tells you without a doubt whether it's rated for PC100 or PC133. You can get it here: or ftp://ftp.heise.de/pub/ct/ctsi/ctspd092.zip
Last year I bought two modules of generic SDRAM and was assured that they were PC 133. I was kinda suspicious though because I could never set the memory bus to anything other than 100 MHz even though I was running a 133 MHz FSB processor. Using that little app, it revealed to me that one of my modules was in fact only rated for PC100. I took out the PC100 module and whoa, I was able to set the memory speed to 133MHz. Took out the PC133 and put back in the PC100 and I was limited to 100MHz again. Moral of the story, for not much more money these days, buy brand name memory like Crucial, Kingston, etc.
Phillip Chee
Learning Commons Technologist
this German PC web site has a nifty utility called ctspd that reads the SPD chip off your SDRAM module and tells you without a doubt whether it's rated for PC100 or PC133. You can get it here: or ftp://ftp.heise.de/pub/ct/ctsi/ctspd092.zip
Last year I bought two modules of generic SDRAM and was assured that they were PC 133. I was kinda suspicious though because I could never set the memory bus to anything other than 100 MHz even though I was running a 133 MHz FSB processor. Using that little app, it revealed to me that one of my modules was in fact only rated for PC100. I took out the PC100 module and whoa, I was able to set the memory speed to 133MHz. Took out the PC133 and put back in the PC100 and I was limited to 100MHz again. Moral of the story, for not much more money these days, buy brand name memory like Crucial, Kingston, etc.
Phillip Chee
Learning Commons Technologist
Actually I'm asking the question on behalf of my friend. My friend's PC has the following configuration :-
1) Intel celeron 533MHZ
2) 64 SD RAM
3) Xcel 2000 LMRT mainboard
4) Seagate 10.2 GB
5) Cyber Drive 50X CDROM
6) 1.44 FDD Drive
She has the problem of PC hangs frequently(> 3 times within an hour) whenever she runs programs like MS Word/Excel. Even yahoo mail will her PC when the email has graphics file attachment. ICQ hangs her PC too but mIRC is ok.
According to the manual found in
The motherboard supports :-
1) Pentium® II 233~500MHz, Celeron 266~433MHz and Pentium® III (Katmai New Instruction) 450~500MHz CPUs.
2) Both 66.6MHz and 100MHz FSB (Front Side Bus) .
3) Only 3.3V SDRAM DIMM modules.
Her processor is Intel celeron 533MHZ which exceeded the motherboard supported range for celeron(266~433MHz). Could it be this the reason why her PC always hang ? I'm not sure about which SDRAM is she using. And what is "3.3V SDRAM" ? Is it version of the SDRAM ? I thought only the speed of the SDRAM makes the difference.
What can be the problem ? Processor ? Memory ? Or over heated ?
Thank you in advance
1) Intel celeron 533MHZ
2) 64 SD RAM
3) Xcel 2000 LMRT mainboard
4) Seagate 10.2 GB
5) Cyber Drive 50X CDROM
6) 1.44 FDD Drive
She has the problem of PC hangs frequently(> 3 times within an hour) whenever she runs programs like MS Word/Excel. Even yahoo mail will her PC when the email has graphics file attachment. ICQ hangs her PC too but mIRC is ok.
According to the manual found in
The motherboard supports :-
1) Pentium® II 233~500MHz, Celeron 266~433MHz and Pentium® III (Katmai New Instruction) 450~500MHz CPUs.
2) Both 66.6MHz and 100MHz FSB (Front Side Bus) .
3) Only 3.3V SDRAM DIMM modules.
Her processor is Intel celeron 533MHZ which exceeded the motherboard supported range for celeron(266~433MHz). Could it be this the reason why her PC always hang ? I'm not sure about which SDRAM is she using. And what is "3.3V SDRAM" ? Is it version of the SDRAM ? I thought only the speed of the SDRAM makes the difference.
What can be the problem ? Processor ? Memory ? Or over heated ?
Thank you in advance
433 MHz Celeron was probably the fastest Celeron processor available when the manual was published.
533 MHz Celeron is probably supported on later motherboard and BIOS revisions. They have the same core voltage - 2.0v.
3.3v SDRAM means the memory uses 3.3volts. That is standard.
A lot of things could be causing your problem including bad memory, a bad motherboard, a bad power supply, or overheating. Xcel 2000 is a PC-Chips motherboard. They have a lot of problems.
On a tech site I used to go to frequently, about 50% of the questions were concerning PC-Chips boards.
You may be able to get this board to work, some people do, but if you want to save yourself a lot of trouble get a GOOD motherboard.
Hope this helps. Good luck.
John
533 MHz Celeron is probably supported on later motherboard and BIOS revisions. They have the same core voltage - 2.0v.
3.3v SDRAM means the memory uses 3.3volts. That is standard.
A lot of things could be causing your problem including bad memory, a bad motherboard, a bad power supply, or overheating. Xcel 2000 is a PC-Chips motherboard. They have a lot of problems.
On a tech site I used to go to frequently, about 50% of the questions were concerning PC-Chips boards.
You may be able to get this board to work, some people do, but if you want to save yourself a lot of trouble get a GOOD motherboard.
Hope this helps. Good luck.
John
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