I was wondering what are differences between "bus speed", "rated bus speed", "stock bus speed"?
I saw in Speccy running on my laptop:
Bus Speed 200.0 MHz
Rated Bus Speed 800.1 MHz
Stock Core Speed 1600 MHz
Stock Bus Speed 200 MHz
Thanks!
“bus speed”, “rated bus speed”, “stock bus speed”
chipsetfsbmotherboardterminology
Related Solutions
First, and most important, I think you're mixing up "actual" and "equivalent" RAM speeds. (That, or you've just worded things oddly.) DDR(2,3) RAM is called such because it performs a read, a write, or whatever, twice per clock cycle, essentially doubling it's actual clock rate. DDR1 RAM, like you have, usually ranges from 100 MHz to 200 MHz in actual clock rate, which amounts to an effective speed of 200-400MHz. CPU-Z shows effective clock speed in all circumstances.
The RAM in your system will 1. all run at the same speed, and 2. run at the lowest supported speed by any one stick of installed RAM. Different sticks of RAM can't run at different speeds in the same system.
Therefore, I believe you might've misread your CPU-Z output, and were instead looking at each stick's capable maximum, rather than it's current running speed.
In the above screenshot from my workstation, I have my DDR2 RAM running at 266 MHz (533 effective).
Your machine is, because of your one 133MHz stick, likely running at 133 MHz, or 266 MHz effective, because of your 256 MB stick. If you were to replace that with a shiny new 200 MHz effective stick, that would then boost your effective RAM clock speed from 133 MHz right now to 200 MHz, or 400 MHz effective.
As far as running RAM faster than your FSB is concerned, this isn't an issue with modern processors. In particular, your AMD HyperTransport-based (you don't have a "FSB") processor has an on-die memory controller, which allows you to run your RAM at any speed you like over or under the FSB speed without issue. Intel-based processors that use a FSB (pre-i5/i7) see some gains from running their RAM at the same speed as their FSB (this is called 1:1 operation), but they're still very minimal. FSB-based processors might not like RAM running slower than the FSB, but faster works fine.
The only things that could affect whether or not that stick of RAM would work are memory timings and DIMM voltage. For the former, memory timings will likely be adjusted to the lower of your two sticks of RAM, just like the frequency. Voltage probably won't be be an issue, as usually only goofy overclocker's RAM needs higher voltages than normal.
Finally, in regards to whether more headroom or more speed is important -- well, you get both more speed and more headroom, in this situation, but in general more headroom is the more desirable trait. RAM speed often has very little effect on modern applications, and a doubling of memory speed never equates to even a 25% boost in performance for most real-world tasks.
So, in short: Yes, you can run that 1GB 400MHz stick fine. You already have a 512MB 400MHz stick in there. Your system'll get a tinge quicker, and you'll have more working space to Get Stuff Done in.
Traditionally, firmware is CPU code that resides on a unmodifiable ROM that is necessary for a hardware device to boot and load an operating system or a binary (software) of choice. Sometimes no choice of a binary is given and one attached to the boot-portion firmware is used.
All CPUs have the classical problem in that, since they fetch instructions from memory, some sort of pre-programmed memory must exist at a fixed address when the CPU starts, so that it can do something automatically on startup. Firmware exists for this purpose. Some firmware also has code that later programs can use for services. BIOS firmware exposes many functions that DOS used for basic input and output (hence why BIOS stands for Basic Input Output System).
The distinction is not totally clear. Some (most) WLAN cards require firmware to be loaded before they will start functioning. However, usually there is a tiny firmware on the device whose job is to do nothing but accept a main "firmware" over the USB bus when the device is started by the operating system, and hand over control when it is loaded. Most people would say all of it is firmware.
Since EEPROMs and flash memory became more common, firmware usually no longer resides in an unwriteable ROM but in flash memory and can be modified. The distinction between firmware and software is blurry today with the advent of flash memory. However, one thing hasn't changed over the years and that is CPUs are still CPUs and require some code, or firmware, to be visible at startup to, well, start up.
CPUs are in more devices than ever before so developing and allowing firmware to be updated in the case of bugs is a big deal now and many hardware devices with a CPU have firmware update interfaces, sometimes undocumented.
A firmware can be used to load an OS. It can contain a boot loader or code that loads a boot loader. It is possible to store an OS image in the same location as firmware and let the boot-time code of firmware load the OS (cell phones do this). PC BIOSes as a rule do not include boot loaders. U-boot (not for PCs) is an example of a "filesystem-aware" firmware that does directly load an operating system.
FIrmwares usually do not have all the features of a full operating system because of the principle that simpler is more reliable. The simplest firmwares simply initialize a minimum of hardware, load a sector or block off of a storage device and throw execution to it. This is simple to program and therefore easy to verify as bug free. Bugs in boot time firmware particularly can spell disaster for a device.
Best Answer
Default Speed at which Front Side Bus aka FSB aka bus runs at.
Speed at which Front Side Bus aka FSB aka bus runs at.
Effective speed of the bus ( recent Intel chipsets are quad pumped, hence 200MHzx4 = 800 MHz)
Stock speed of your processor core.
( If you're wondering why "stock speed" v/s just "speed" - speed would refer to the overclocked speed ).