How to Find the Actual RAM Bus Speed?

[nrjperera]

Hi,

 

My laptop has a 2GB Kingston 1Rx8 PC3 12800s RAM.

I'm looking to add an extra 2GB RAM. 

 

I used CPU-Z to find the bus speed of the RAM.

It showed the speed as 532.3mhz. Which equals to a total speed of 1066mhz.

 

But when I looked up for a DDR3 12800s RAM with 1066mhz speed, nothing showed up.

All the results had 1600mhz speed. And the 1066mhz results showed 8500s instead of 12800s.

 

What is the actual bus speed here?  Should I get 1066 or 1600mhz? and what does this "12800s" part mean?

 

Help me out guys.

Thanks.

[sc302 Veteran]

http://www.crucial.com

 

It will tell you what you can put in....you can run the scanner and it will scan your system then bring you to a page where it guarantees compatibility with your system and speed your system will accept up to.

[Tomo]

Sounds like the motherboard isn't running the memory at it's fastest speed, 12800 / 8 gives you 1600Mhz and should have a clock speed of 800Mhz (Double date rate gives 1600Mhz). 532.3Mhz equates to 1066Mhz RAM (1066 * 8 = 8500)

 

It's possible the motherboard cannot run at the higher speed so reduces the speed of the memory to one that it can cope with.

[nrjperera]

http://www.crucial.com

 

It will tell you what you can put in....you can run the scanner and it will scan your system then bring you to a page where it guarantees compatibility with your system and speed your system will accept up to.

 

I tried the Crucial scan.

But they don't seem to have my laptop model.

 

Gave me this message - "Crucial currently does not have any compatible upgrades available for your particular system."

Sounds like the motherboard isn't running the memory at it's fastest speed, 12800 / 8 gives you 1600Mhz and should have a clock speed of 800Mhz (Double date rate gives 1600Mhz). 532.3Mhz equates to 1066Mhz RAM (1066 * 8 = 8500)

 

It's possible the motherboard cannot run at the higher speed so reduces the speed of the memory to one that it can cope with.

 

So, should I get 1066mhz 8500s?

[sc302 Veteran]

Curious, what laptop model do you have??

[nrjperera]

Curious, what laptop model do you have??

 

Toshiba Satellite C850D

[Tomo]

So, should I get 1066mhz 8500s?

It doesn't matter, the higher speed modules will slow down to meet the requirements of the motherboard.

[sc302 Veteran]

which 850D there are quite a few of them..

 

(you may have to look on the bottom....there is probably a sticker that has the complete model C850d-xx or C850d-xxx or C850d-xxxxxx  or C850d/xx)

[nrjperera]

It doesn't matter, the higher speed modules will slow down to meet the requirements of the motherboard.

 

Thanks. I will try it out.

BTW is it OK to pair RAMs from different manufacturers? for example Kingston with Samsung?

which 850D there are quite a few of them..

 

(you may have to look on the bottom....there is probably a sticker that has the complete model C850d-xx or C850d-xxx or C850d-xxxxxx  or C850d/xx)

 

It's this one - http://www.toshiba.co.uk/discontinued-products/satellite-c850d-11f/

The page shows 1066mhz. But the sticker on my RAM says 1600mhz.

Now the problem is, would it work if I add another 1600mhz RAM?

[sc302 Veteran]

http://www.crucial.com/usa/en/compatible-upgrade-for/Toshiba/satellite-c850d-11f

 

According to cruical you can go up to a max of 8GB with a max speed of 1866...your system is compatible with PC3-14900.  The kit is $73.99 usd.

 

http://www.crucial.com/usa/en/satellite-c850d-11f/CT3766540

[nrjperera]

http://www.crucial.com/usa/en/compatible-upgrade-for/Toshiba/satellite-c850d-11f

 

According to cruical you can go up to a max of 8GB with a max speed of 1866...your system is compatible with PC3-14900.  The kit is $73.99 usd.

 

http://www.crucial.com/usa/en/satellite-c850d-11f/CT3766540

 

Hmm.. That's Odd. Wonder why my current 1600 RAM shows up as 1066mhz on CPU-Z.

I will go for 1600mhz then. Anyway, thanks for your help. 

[Tomo]

Thanks. I will try it out.

BTW is it OK to pair RAMs from different manufacturers? for example Kingston with Samsung?

 

It's ok but I would try and match the RAM to the same model if possible to avoid any issues.