mm0

原帖由 gabrielM 於 2008-3-18 15:22 發表 also i have chucked the d520 with 4g, guess what?  only 3318 mb is usable in bios.  kinda really disappointing.

just wonder have you reported this to dell?  maybe they can fix it with a bios update.

奈河橋船夫

依家梗係買IBM  好用好多  料足 保養好

ciel

Addressing Memory With 4-GB Configurations (32-bit Operating Systems Only)

...... computer supports a maximum of 4 GB of memory when you use two 2-GB DIMMs. Current 32-bit operating systems, such as Microsoft® Windows® XP, can use a maximum of 4 GB of address space; however, the amount of memory available to the operating system is less than that installed. Certain components within the computer require address space in the 4-GB range.
Any address space reserved for these components cannot be used by computer memory.
......
The following components require memory address space:

    * System ROM
    * APICs
    * Integrated PCI devices, such as network connectors
    * PCI cards
    * Graphics cards
    * PCI Express cards (if applicable)

At start-up, the BIOS identifies the components that require address space. The BIOS dynamically calculates the amount of reserved address space required. The BIOS then subtracts the reserved address space from 4 GB to determine the amount of usable space.

    * If the total installed computer memory is less than the usable space, all installed computer memory is only available for use by the operating system.

    * If the total installed computer memory is equal to or greater than the usable address space, a portion of installed memory is not available for use by the operating system.

http://supportapj.dell.com/suppo ... en/UG_en/memory.htm

See also
用4g ram行xp的朋友，你地最多show到幾多出黎﹖

barryw

這個是 Address mapping 問題.
32 bit OS, 2^32 = 4G. 即是最多可以 addressing 4G 的地址. 所以, 理論上, 可以用到  4GB RAM.

但由於是用  memory addressing 的方式去控制 hardware. 即是, 很多hardware 也會給了一段指定的地址給它, 好讓 OS 可以直接用 address 去 visit 它, 所以, 在這些 reserve 了的 address, RAM 和 Hardware address 是相同地址, 那段 RAM 便用不到.

越多 hardware, 便會 map 了越多的 address, 相對地, 便少了越多可用 RAM. 一般不過 3.5GB RAM. 3.25左右是常見的.

這個問題不易解決, 因為是整體 hardware design 的問題. (即是 chipset 的 design, 不是 dell 的 design).

akg

點教color?  可否比少少instruction? thanks

原帖由 patrickwong55 於 2008-3-15 19:35 發表


Update 咗 driver  可以較 colour 啦........

http://supportapj.dell.com/suppo ... 0&fileid=205126

mm0

原帖由 akg 於 2008-3-19 11:34 發表
點教color?  可否比少少instruction? thanks

try the "color correction" tab