Re: 2.6.2: P4 ClockMod speed

From: dual_bereta_r0x
Date: Wed Feb 25 2004 - 20:31:58 EST


Dominik Brodowski wrote:


That's not the point: some hardware (e.g. ARM) needs different memory
settings and different settings of the LCD controller for different CPU frequencies, as the Front Side Bus of the CPU is closely related to the CPU frequency. On x86, all cpufreq techniques I've
seen so far do not modify the FSB [*], so memory settings etc. do not need
to be modified.

Dominik

[*] or scaling the FSB didn't work...

In x86 world, this info is wrong. The *multiplier* is locked inside processor (Intel P4) or by some "dips" on cpu core (AMD Athlon XP) -- unless you have such as "enginering samples", with didn't have this lock --, but front-side-bus is changeable via MoBo BIOS. Also, if you just add 0.5v in your CPU you can made it running faster than designed. The same applies to memory. That's why we bought DDR533 mems to run in DDR400 hardwares. We increase FSB and our mems could run with this new FSB.

Again, showing *max* from manufacturer instead of *actual* speed is wrong. Even if the machine has or not capabilities to run with more/less power than it has designed for, is not up to the OS decide it. The OS should run or not, but the user has chosen this path; it must only tell him what's *really* happening. "Your actual clock differs from manufacturer. Its *your* fault if any component fail or malfunctions/bugs arrives because of this."

--
dual_bereta_r0x -- Alexandre Hautequest
ArenaNetwork Lan House & Cyber -- www.arenanetwork.com.br
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