RAM Question - Data Bus Speeds/Memory Speed

was looking for some new RAM, as my computer's pretty slow. I found some for a good price, but had a question.

According to my specifications, by Data Bus Speed is 533 MHz, however my Memory Speed is 333 MHz. The RAM I'm looking at has a "speed" of 400 MHz.

First of all, what "speed" does this apply to? Data Bus Speed or Memory Speed? Second of all, does it matter? If my computer doesn't read it fast enough, is it incompatible, or just not as fast as it could be?

Thanks for your help!

Below are your memory specs - i would say you would probably be better off with modules all the same type and speed - you can find this on the sticks inside the case - your specs aint that bad i think 4gb of memory would work better - how often do you defrag your hard drives - i think default is weekly, so this shouldnt be too bad. Your hard drives could be a limitation also, but with 4gb of memory once all your programs are loaded into memory it will run reasonably well.

Memory
Architecture
Dual Channel DDR SDRAM
Memory connectors
Four
Memory capacities
128-, 256-, 512-MB or 1-GB
Minimum memory
128-MB DDR SDRAM
NOTE: Between 32 and 64 MB of system memory may be allocated to support graphics, depending on system memory size and other factors.
Maximum memory
4 GB
Memory type
PC2700 (333-MHz) or PC3200 (400-MHz) DDR SDRAM
(non-ECC)

Memory

Architecture
Dual Channel DDR SDRAM

Memory connectors
Four

Memory capacities
128-, 256-, 512-MB or 1-GB

Minimum memory
128-MB DDR SDRAM
NOTE: Between 32 and 64 MB of system memory may be allocated to support graphics, depending on system memory size and other factors.

Maximum memory
4 GB

Memory type
PC2700 (333-MHz) or PC3200 (400-MHz) DDR SDRAM
(non-ECC)

http://support.ap.dell.com/support/e...i/sm/index.htm

http://support.ap.dell.com/support/t...gen&~ck=anavml

So, I guess my question is, does the speed matter? If I buy the RAM, will it work or not?

Unless your gaming you wont notice any speed difference between 333 and 400.

And if I am gaming? XD

I can't recall the details of SDRAM as it has been several years since I dealt with it.

If your existing RAM is 333 speed, it may well be that even if you bought 400, the new 400 would run at 333---defaulting to the lowest speed of your existing sticks. I'd guess you have 333 as it would have been cheapest for Dell at the time your PC was built.

You could probably run an app like CPU-Z to get more details on your existing RAM.

The information CPU-Z gave me didn't seem like it was what I was looking for, but here it is in case someone else can interpret for me.

General
Type: DDR
Size: 2048 MBytes
Channels: Single

Timings
DRAM Frequency: 166.3 MHz (varied between 166.1 and 166.3)
FSB:|RAM: 4:5
CAS# Latency (CL): 2.5 Clocks
RAS# to CAS# Delay (tRCD): 3 Clocks
RAS# Precharge (tRP): 3 Clocks
Cycle Time (tRAS): 7 Clocks

Thanks for all your help!