I just don't get it... Am I stupid or what? HELP Please!

[cho1594]

Hi!

I am considering upgrading my computer and I have to buy new MBO, CPU & RAM. I have decided to buy E8400 processor (FSB 1333 Mhz) and for MBO I can't decide between ASUS P5E & Gigabyte X38-DS5 (X38 chipsets). Now, I don't know which RAM should I buy. I am considering one of these three models:

DDR2 2GB (2x1GB kit) PC6400 (800MHz) OCZ, Platinum XTC, DC kit
DDR2 1GB,PC8500 (1066MHz) CRUCIAL Ballistix
DDR2 2GB (2x1024) PC6400 Corsair (800MHz) TWIN2X2048-6400, CL5

As I want my CPU and RAM to work in sync mode I just don't get the FSB/RAM thingy. What's the real FSB frequency of E8400 CPU? Is it 4x333MHz or some other frequency? Does it mean that my memory would work on 667 MHh (2x333Mhz) or it would work on 400 MHz? The confusing part is my current configuration info regarding FSB/RAM freqeuncies (Athlon X2 4200+ @2200 MHz, 2x1 GB PC6400 Kingmax @ 800 MHz). When I run CPU-Z I get this info:

CPU

Core Speed : 2210.6 Mhz
Multiplier: x11
Bus Speed: 200.9 MHz
HT Link: 1004.6 Mhz

RAM

DRAM freq: 368.4 Mhz
FSB:RAM: CPU/6 (?????) (how could this be while the FSB is 200.0 MHz)

I would appricate if someone could explain this FSB/DRAM mystery. If I buy
E8400 with FSB 1333 MHz does it mean that if I buy PC6400/PC8500 RAM I would have to overclock it to 1333 MHz to get it work in sync mode or I should do anything else?

Many thanks in advance!

 

[Shiggity]

Well the ram speed is directly related to the FSB speed and the FSB of 1333 of the motherboard means you can run Ram up to 1333 speed and it will be 100% effective. You don't have to make the ram do exactly 1333.

(1200 speed ram would be a waste on a mobo that only supported up to 1066 speed, etc. Most people don't run their ram too high over 1000 though.)

Let's say you OC your E8400 to 400x9 (3.6ghz). The speed of the memory is based on the divider you choose in the BIOS. (1:1 , 6:5 , 3:2 , 4:3 , 5:4) (Ram:FSB)

400x9 with a 1:1 divider would give you memory of 800mhz
400x9 with a 4:3 divider would give you memory of 1067mhz
etc etc

I'm pretty sure the part you're confused on is the divider aspect of ram speed (all you do is pick the divider in the bios and it automatically adjusts the ram speed). They have dividers in there because certain CPUs only have certain multipliers and it allows you to put your ram at many many different speeds and variations.

Once you start overclocking it becomes much clearer, I was confused as hell by this when I first started as well.

 

[vlaszlo]

You are mixing AMD and INTEL stuff... search more

 

[cho1594]

You are mixing AMD and INTEL stuff... search more

Very helpful answer, vlazlo...

 

[cho1594]

Well the ram speed is directly related to the FSB speed and the FSB of 1333 of the motherboard means you can run Ram up to 1333 speed and it will be 100% effective. You don't have to make the ram do exactly 1333.

(1200 speed ram would be a waste on a mobo that only supported up to 1066 speed, etc. Most people don't run their ram too high over 1000 though.)

Let's say you OC your E8400 to 400x9 (3.6ghz). The speed of the memory is based on the divider you choose in the BIOS. (1:1 , 6:5 , 3:2 , 4:3 , 5:4) (Ram:FSB)

400x9 with a 1:1 divider would give you memory of 800mhz
400x9 with a 4:3 divider would give you memory of 1067mhz
etc etc

I'm pretty sure the part you're confused on is the divider aspect of ram speed (all you do is pick the divider in the bios and it automatically adjusts the ram speed). They have dividers in there because certain CPUs only have certain multipliers and it allows you to put your ram at many many different speeds and variations.

Once you start overclocking it becomes much clearer, I was confused as hell by this when I first started as well.

But what if I leave FSB running on 333Mhz and set the divider 1:1 with
PC6400/PC-8500? On which frequencies would then RAM work?

 

[th3]

Vlazlo is kinda right, you are mixing up Intel vs AMD memory speeds. On your AMD memory speed depends on CPU speed, just forget about it for now as it does not apply to Intel.

FSB at 333 and divider 1:1 will run your RAM at 667. However theres no reason to do use the 1:1 when at low FSB speeds with fast RAM, in theory the optimal divider is 1:2, higher memory speed will give you more performance in some apps/benches, WinRARs built in benchmark being the classic example.

 

[cho1594]

Vlazlo is kinda right, you are mixing up Intel vs AMD memory speeds. On your AMD memory speed depends on CPU speed, just forget about it for now as it does not apply to Intel.

FSB at 333 and divider 1:1 will run your RAM at 667. However theres no reason to do use the 1:1 when at low FSB speeds with fast RAM, in theory the optimal divider is 1:2, higher memory speed will give you more performance in some apps/benches, WinRARs built in benchmark being the classic example.

I was just trying to point out with my current AMD configuration that it's a bit confusing. The AM2 configuration will be used as a server for downloading binaries, torrents etc, while a new socket 775 will be used as a client computer. Which memory should be optimal for E8400 (FSB 1333 Mhz) and a
X38 motherboard (probably ASUS P5E) or should I better buy P35 chipset motherboard?

DDR2 2GB (2x1GB) PC6400 (800MHz) OCZ, Platinum XTC DC kit
DDR2 2GB (2x1GB) PC8500 (1066MHz) CRUCIAL Ballistix
DDR2 2GB (2x1GB) PC6400 (800MHz) Corsair TWIN2X2048-6400 CL4

If I decide to buy OCZ is this memory overclockable? What about CB memory? I have read on this forum that many people are experiencing issues with them?

 

[tuskenraider]

DDR2 2GB (2x1GB) PC6400 (800MHz) OCZ, Platinum XTC DC kit
DDR2 2GB (2x1GB) PC8500 (1066MHz) CRUCIAL Ballistix
DDR2 2GB (2x1GB) PC6400 (800MHz) Corsair TWIN2X2048-6400 CL4

If I decide to buy OCZ is this memory overclockable? What about CB memory? I have read on this forum that many people are experiencing issues with them?

I've owned 2 out of the 3 you listed. My OCZ kit does about 980mhz at 2.2V, the 2 Corsair sets I've had both have done about 1030mhz at 2.1V. Never tested with higher voltage though.

 

[Evilsizer]

the balli's are the most overclockable, though they run hot you will need active cooling on them. what kind of fsb are you looking to run?

 

[cho1594]

the balli's are the most overclockable, though they run hot you will need active cooling on them. what kind of fsb are you looking to run?

Well, I am considering to OC just a bit while I just want to optimize CPU/RAM efficency.I would leave the default FSB frequencies @ 333 MHz but the my RAM will work under it's default frequency. Is E8400 OC-able to 400 MHz FSB? The I suppose my RAM will work at 800 MHz, would that be correct?
I have to decide between the three motherboards:

Gigabyte GA-X38-DS4

http://www.gigabyte.com.tw/Products/Motherboard/Products_Overview.aspx?ProductID=2736

Gigabyte GA-X38-DS5

http://www.gigabyte.com.tw/Products/Motherboard/Products_Overview.aspx?ProductID=2672

ASUS P5E

http://usa.asus.com/products.aspx?l1=3&l2=11&l3=572&l4=0&model=1873&modelmenu=2

I know that balli's are good OC's but I've read the post few lines below about problems with balli's so I am a bit sceptical now should I consider buying it or not.

 

[cho1594]

I've owned 2 out of the 3 you listed. My OCZ kit does about 980mhz at 2.2V, the 2 Corsair sets I've had both have done about 1030mhz at 2.1V. Never tested with higher voltage though.

If I decide to raise FSB/RAM frequncies does it mean neccesarily that I must raise FSB/RAM voltages? Should I manually set the RAM timings too?

 

[Evilsizer]

well imo then get the ram in my sig, it doesnt use micron ic's. they use promos based ic's and at stock voltage all 4 1gig sticks up to ddr2-980 4-4-4-10. my current bios doesnt like 4-4-4-8 even at ddr2-800, so i had to loosen that up a touch.

though if you really want some head room consider the 4gig kit from Gskill. ddr2-1000 5-5-5-15 [email protected] only $114 on newegg right now.