# Is it possible to upgrade a Windows 7 computer? **URL:** \ **Category:** Factual Questions\ **Tags:** computer-hardware\ **Created:** [January 17, 2024, 7:48pm UTC](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235 "2024-01-17T19:48:27Z")\ **Posts on this page:** 4\ **Page:** 3
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [January 22, 2024, 6:56am UTC](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235/41 "2024-01-22T06:56:59Z")
> [@Askance](#): > > Something else was using that 1.5gb you were missing. The issue is that the 4 GB of address space has to cover _everything_ addressable by the CPU–and that includes things that are not main memory. In particular, in those days video memory would be fully mapped by the CPU. If you had a 512 MB video card, then you would lose 512 MB of address space. More if the video card had more memory. **Darren\_Garrison** possibly had a 1.5 GB video card, or two 768 MB cards, or perhaps a 1 GB card and some other device that used address space. 64-bit systems have plenty of address space to go around. And eventually (I should remember when, but I forget the timeframe), video card drivers stopped mapping all of video memory, and instead just had a relatively small (usually 256 MB) segment of mapped memory. Though this is changing now with “resizable BAR”. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [January 23, 2024, 6:17pm UTC](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235/42 "2024-01-23T18:17:49Z")
I believe PAE, aka Physical Address Extensions, allows use of the full 4GB of memory. I don’t think Windows XP uses it, but later 32-bit versions do. I know modern 32-bit versions of Linux use PAE, which broke compatibility with really old CPUs. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [January 23, 2024, 11:00pm UTC](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235/43 "2024-01-23T23:00:25Z")
Correction; Windows XP did allow PAE. However, it ran into problems with drivers in trying to map memory beyond 4GB. So that feature was disabled in Service Pack 2 and beyond. Subsequence versions of Windows also stuck with the 4GB barrier–though it’s unclear to me if peripherals could be loaded into a higher address space. ---
**Author:** ![ralfy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ralfy/32/600_2.png) [@ralfy](https://boards.straightdope.com/u/ralfy)\ **Post date:** [January 26, 2024, 4:52am UTC](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235/44 "2024-01-26T04:52:50Z")
It’s best to use newer versions of systems in order to deal with issues involving malware, etc. [Previous page](https://boards.straightdope.com/t/is-it-possible-to-upgrade-a-windows-7-computer/996235.md?page=2)