i heard that 32 bit OS only reconize up to 3GB of ram. is this true? because im on windows vista-32 bit and
i plan on upgrading my mobo and buying 4 gb of ram. and i want to make sure im using all 4 gb.
32-bit means it can only “see” 2^32 (2 to the 32nd power) = 4GB memory spaces.
The computer has to be able to see the RAM + VRAM + other devices on Motherboard, etc.
e.g. If you have 1GB VRAM and “other devices” takes up 0.3GB, you will only be able to use a max of 2.7GB (4 - 1 - 0.3 = 2.7) .
In this case, if you install 3GB, you waste 0.3GB…if you install 4GB you waste 1.3GB!
If this is any indication that 64-bit is the wave of the future and 32-bit will be “obsolete”…
There appears to be a shift taking place in the PC industry: the move from 32-bit to 64-bit PCs.
We've been tracking the change by looking at the percentage of 64-bit PCs connecting to Windows Update, and have seen a dramatic increase in recent months. The installed base of 64-bit Windows Vista PCs, as a percentage of all Windows Vista systems, has more than tripled in the U.S. in the last three months, while worldwide adoption has more than doubled during the same period. Another view shows that 20% of new Windows Vista PCs in the U.S. connecting to Windows Update in June were 64-bit PCs, up from just 3% in March. Put more simply, usage of 64-bit Windows Vista is growing much more rapidly than 32-bit. Based on current trends, this growth will accelerate as the retail channel shifts to supplying a rapidly increasing assortment of 64-bit desktops and laptops… PC Accelerators built into Windows Vista, such as Windows SuperFetch, improve performance by keeping commonly used programs in memory, even when the program is closed. More memory capacity on 64-bit PCs allows SuperFetch to do its job more efficiently. http://windowsvistablog.com/blogs/windowsvista/archive/...
Considering this, SuperFetch is probably the most significant feature that distinguishes Vista from all other OS's for users of all walks. Many other features won't be noticeable or even used by the common person (that is until commercial developers start using WPF/WFC etc., and even more DX10). So why not take advantage of it since RAM is so cheap?
Some interesting hardcore 64-bit info:
...all 64-bit versions of Microsoft operating systems currently impose a 16 TB limit on address space and allow no more than 128 GB of physical memory due to the impracticality of having 16 TB of RAM. Processes created on Windows Vista x64 Edition are allotted 8 TB in virtual memory for user processes and 8 TB for kernel processes to create a virtual memory of 16 TB. http://zone.ni.com/devzone/cda/tut/p/id/5709
To put things in perspective, this is what 64-bit does...
What are the advantages of 64-bit computing?
In early testing of 64-bit support in Photoshop for Windows®, overall performance gains ranged from 8% to 12%. Those who work with extremely large files may realize noticeably greater gains in performance, in some cases as dramatic as ten times the previous speed. This is because 64-bit applications can address larger amounts of memory and thus result in less file swapping — one of the biggest factors that can affect data processing speed. http://www.adobe.com/products/photoshop/photoshop/faq/?...
Good post above. Short answer is no, no MS consumer 32 bit OS presently will be able to use all 4 gig. You get about three of it when you have a video card with a lot of RAM - hence the reason 64 is so popular now -RAM is cheap and Vista 64 just works.