It used to be simple. A FSB of 66/100/133 multipled by a cpu ratio equated to CPU MHZ. That's about when I stopped reading up on motherboard technology. I could tweak either the FSB or CPU multiplier and achieve results (albeit sometimes disasterous). I now have a MSI MS-6580 motherboard. I have a Celeron 1.7GHZ CPU and (I believe) PC2100 DDR RAM. I have the following settings of interest:

CPU Ratio selection: This is locked (@ 17)
CPU FSB Clock: Goes between 100-200
DRAM frequency: This is under another menu topic and I have the following selections SPD, 200MHz, 266MHz, 333MHz (@533MHz FSB), Auto.

My settings are:
CPU Ratio selection: locked
CPU FSB Clock: 118
DRAM frequency:Auto.

I'll offer the following specs from my manual:
CPU
�� Supports Socket 478 for Intel® Pentium 4/Celeron processors
�� Core Frequency from 1.4 GHz to 2.8 GHz and up* (*not tested yet)
Chipsets
�� Intel® 845GE chipsets
- AGP 4x slot (1.5v only)
- Integrated graphic controller
- Support 100/133/166 MHz FSB
- Support 400/533 MHz Intel NetBurst micro-architecture bus

I'm looking into a new CPU by I notice some of them specify a 533MHZ FSB. Do I have that?
Plus, I am trying to understand what I have to do to make my CPU FSB clock as high as possible. Anything over 125 causes havok. I expected that as my CPU is running at 2GHZ. Does this have anything to do with my RAM?
I guess my main problem is I don't understand the relation between my FSB and RAM. How fast is my RAM running and can I buy a CPU that specifies a 533 MHZ FSB?