Increased FSB, CPU no real change, why?

Hello guys, first post so don't be too harsh lol. I read Aces guide.. very informative! Ty.

My partner has built the following PC and I just had to have a quick bash at the FSB. This is what she built. (And made a lovely job of it too!)
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OPERATING SYSTEM
Windows XP Pro SP2

MAINBOARD
Board: Asrock 775Dual-915GL 1.00
Bus Clock: 200 Mghz
BIOS: American Megatrends Inc. P1.30 10/12/2005

PROCESSOR
3.40 Ghz Pentium 4 (37 centigrade idle)
2 MB L2 cache
Thermaltake HSF

HDD
Maxtor 250GB Sata

MEMORY
1024 Megabytes Installed Memory
Slot '0' has 512 MB OCZ DDR 400
Slot '2' has 512 MB OCZ DDR 400

Display
GeForce 7300 LE

PSU
550W (32AMP 12V Rail)
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Anyway, I upped the FSB to 205Mhz (didnt expect much difference!) So I then went 220. Booted fine but CPU still showed at 3.40 with various monitor progs. Upped to 250 and still all fine but still 3.4Ghz CPU. Scratched my head and upped to 300Mhz. Still booted fine. No temp change! But now the CPU seemed to be running at 3.41Ghz.

(Yes I know it was a bit silly but I couldnt understand why it made such little difference when I should have been running at 5.1Ghz by then lol)

Evntually I gave up and rebooted, checked the FSB (300Mhz) (Multiplier 17) (Ram 400Mhz) But CPU still 3.41Ghz. So I put the FSB back to 200Mhz and came here lol. Anyone any ideas what happened, (or rather what didn't happen!)

Great forum by the way, hoping to learn a lot!
Jack and Elly.

P.S. I did wonder if it was throttling but there was no sign of it and all temps remained fine. Am I missing something very very simple! D

 

I dont think your changes are being saved in the bios, read carefully when you exit the bios. ed

 

Putting the FSB any higher than 240 would be stupid in my opinion, unless you have kick-ass cooling.

But yes, tunered is right, you aren't saying the settings.

 

Ty for the replies Tunered and Joshcrick. (I agree it was stupid Josh but I would not have done it if I wasn't fairly certain that nothing was happening.) I saved settings with F10 before exiting and on each reboot, the settings in bios were those that I had set, so I have no idea lol. Is it possible for the bios to report 250MHZ for example, but not actually be running at that? The funny thing is, the CPU report DID change on 300Mhz, but only from 3.40 to 3.41. Anyway, ty for the replies. If I figure out what happened I will post it. Off to bootsale now )

 

Hi Fautly Basil!

Please enter your bios and be sure to disable any energy saving options that might be hindering your OC, such as speed stepping! Speed stepping lowers the voltage and the clock settings of your CPU when the system is idle, which is why you may not be seeing the clocks change. Conversly, you could try running a program such as prime95, and then run CPU-Z (while prime is running) to see if it is running at full speed. While I cannot be sure that your P4 has speed stepping, as the first intel chip I have ever worked with is core duo, it would be worth a shot!