Newbie question about FSB, CAS

[Guid0]

OK I have been reading about people talking about changing the CAS level. I have a Abit KT7Raid board. IS that the setting in the bios that the options are turbo,8/10n's,normal,ect...

also could someone explain to me how the FSBworks

IE i have my system set @ 100/33..is that 133 FSB?
if i wanted to change my FSB 150 would it be 117/33

if someone could clue me in i would be much apreciative.

Guid0

[WillysNut]

Very good questions!

The setting 100/33 denotes the FSB and PCI speed in MHz. 100 being the Font Side Bus speed and 33 being the PCI bus speed. FSB is the speed in MHz between the CPU and the Northbridge on your motherboard. It's how fast, in MHz, data travels on the wires (the bus). PCI speed is the speed between the components you have plugged into your slots and the southbridge chip.

Under "Advanced Chipset Settings"... If you're using a 133Mhz memory, leave your settings to "Turbo". If your using 100MHz memory, try Fast, Medum and Turbo.

There should be an additional CAS setting below the Medium/Turbo/Fast settings that says CAS time or CAS latency. It should either read 2 or 3. Changing the setting to 3 lowers the timing of the memory and allows for higher FSB settings; greater stability.

Not sure what chip you have but multiply the FSB setting by the multipler of your CPU. If you have an Intel CPU, your multiplier is locked. So...

Example: 8.5 mult. x 100 fsb = 850MHz
8.5 x 117 = 994MHz
8.5 x 150 = 1275Mhz

If you have an AMD cpu that is unlocked, you can change the multipler component of the math.

8.5 x 100 = 850
8 x 117 = 936
7.5 x 150 = 1125

Hope this helps!

[Sonny]

The bad news is that your board has the KT133 chipset that doesnt like the FSB over 115MHz/230DDR

[Guid0]

Thanx Guys that was an excelent explanation.... i had just ordered me some pc150 ram(which seems as thoughit will not be pushed to it's capacity after seeing Sonny's post)either way the CAS thing was bothering me. one sight would say 222 another would say 232 and so on... i just wanted to know how to determine what i had. I do have a t-bird which is OC'd to 1050, but that's it's limit with stability... i tried to go a bit more and i corrupted my raid array...no biggie , but kinda sucked a little....either way hope that i might get a cople more cycles out of my junk after this new memory arrives... thanx again, Guid0