Realizing that an old laptop I have is working at slow ram bus speed

DDR stands for Double Data Rate. The bus speed is 800 mhz which then gets doubled to 1600 mhz actual RAM speed.

What is the difference between SDRAM, DDR1, DDR2, DDR3 and DDR4? - Support & Download

See the chart at the end of the article.

NavyLCDR said:

DDR stands for Double Data Rate. The bus speed is 800 mhz which then gets doubled to 1600 mhz actual RAM speed.

What is the difference between SDRAM, DDR1, DDR2, DDR3 and DDR4? - Support & Download

See the chart at the end of the article.

the article doesnt cover as to when the bus speed drops behind expectations .
it does state that DDR3 has various speed starting from 1066 MHz up till 1600 MHz , now this seems a little outdated as now that stretched to cover 1866 MHz and 2133 MHz . so problem is while the laptop is DDR3 and laptop supports 1066 MHz speed the system is running at 800 MHz rather despite everything being rightly in place and the rams are even of higher bus and variable speeds (2x4 DDR3 1333 MHz) . so why is it operating at such a low speed ?

You don't provide the specs for the laptop. My guess is that the chipset/motherboard is limited to 800 mhz bus speed:
Bus Speed | HowStuffWorks

2x4 DDR3 1333 MHz (that should be MT/s)
If they are marked as 1333 then the bus speed is half that, 667 MHz as shown by CPUID.

CPUID should show a list of JEDEC profiles the highest of which should be 667 MHz.

What should show in Task Manager is 1333 MHz.(that should be MT/s) but that is how MS chooses to display it.

Your old laptop specs are up to 1066 MHz (that should be MT/s) or 'speed'.
The highest bus speed supported is 533 MHz (PC3-8500).

You can't do much with a laptop in the BIOS/UEFI it will auto select the highest suitable JEDEC profile.
If your Memory modules have higher JEDEC profiles than specified for your hardware(533 MHz), it won't go there.

Helmut said:

2x4 DDR3 1333 MHz (that should be MT/s)
If they are marked as 1333 then the bus speed is half that, 667 MHz as shown by CPUID.

CPUID should show a list of JEDEC profiles the highest of which should be 667 MHz.

What should show in Task Manager is 1333 MHz.(that should be MT/s) but that is how MS chooses to display it.

Your old laptop specs are up to 1066 MHz (that should be MT/s) or 'speed'.
The highest bus speed supported is 533 MHz (PC3-8500).

You can't do much with a laptop in the BIOS/UEFI it will auto select the highest suitable JEDEC profile.
If your Memory modules have higher JEDEC profiles than specified for your hardware(533 MHz), it won't go there.

people for god sake read me , i have rams that can support up to 1333 MHz in dual channels and a system that supports up to 1066 MHz in dual channels , the rams are multiprofile and can support the 533 MHz per single chip , yet however task manager and cpu-z both report i am running at 800 MHz dual bus and 399 Mhz single chip respectively . so what to do to boost the bus to full potential which is 1066 and 533 ??

You haven't even provided us with the make/ model of the laptop so the specifications can be checked out. We don't know the CPU nor the motherboard chipset. We have not seen the actual output of CPU-Z. Therefore we cannot possibly begin to offer you valid suggestions because you have given us nothing to work with. Good day to you, sir.

NavyLCDR said:

You haven't even provided us with the make/ model of the laptop so the specifications can be checked out. We don't know the CPU nor the motherboard chipset. We have not seen the actual output of CPU-Z. Therefore we cannot possibly begin to offer you valid suggestions because you have given us nothing to work with. Good day to you, sir.

well i didn't get any requests to provide anything more mind you i thought the figures i posted seems about the whole case , but there , i have updated the opening post hope this would help a bit .

The max bus speed for your computer is 800 mhz. To my knowledge in dual channel mode that gets divided between the two channels, that's why single channel in CPU-Z is showing 400mhz. The max memory speed supported by the computer is 1066. So, if you had a single RAM stick, the bus speed would actually drop to 533.

Right now in dual channel mode you have an effective memory speed of 1600 mhz with DDR RAM.

NavyLCDR said:

The max bus speed for your computer is 800 mhz. To my knowledge in dual channel mode that gets divided between the two channels, that's why single channel in CPU-Z is showing 400mhz. The max memory speed supported by the computer is 1066. So, if you had a single RAM stick, the bus speed would actually drop to 533.

Right now in dual channel mode you have an effective memory speed of 1600 mhz with DDR RAM.

all that math don't add up sir , i still have the good old 3 GBs rams that shipped with the laptop and they are able to achieve the 1066 MHz and 533 MHz per single chip .