Windows XP forum: Windows XP computer still runs slow even after a clean install?!

I did not get to read all the replies so forgive me if I repeat a previous suggestion.

I agree your computer should be running very fast.

You may want to consider updating your BIOS and even resetting the CMOS by removing the CMOS battery. This has cured similar problems I had.

I had the same thing my xp was kinda sluggish even after a recovery. Then I added some memory, it perked up substantially. You should try the 4gb of extra maximum combined with the onboard 8gb and some from ? I forgot. But if you bring the memory up to the maximum without going over it runs great. xp home sp2

Performs just as nice as new. Well, it was XP SP2 when new so something is off here. Look around and read
http://forums.cnet.com/7723-6122_102-510824.html where we POP THE HOOD and found it.
Bob

XP recognizes at least 3.5 Gbs of RAM, or at least not quite 4Gbs. That is been in the MCSE books for years!

These are older 32-bit-only machines. All machines with a 64-bit processor (and compatible motherboard with a BIOS made for accepting a 64-bit processor, i.e. not a 32-bit motherboard with an adapter to install a 64-but processor) will recognize more than 2GB.

And you'll get almost 4GB usable in the OS, if you use it this 64-bit machine with a 32-bit OS, even if each process is invidually bound to a 2GB limit (the rest will be used by concurrent processes, or for mapping the PCI hardware, or could be usable as a system cache with a driver, or as memory used for graphics or other similar devices needing more memory (by swapping 64-bit memory pages in the virtual 32-bit space, specifically in the driver, just like what EMMS did in the old MSDOS and Windows 3.x and Windows 95 time which allowed 16-bit applications to use all the 32-bit space within a virtual 16-bit space). It is possible only because the OS just needs to reserve some pages in the virtual 32-bit space for allowing it to page-in/page-out some 64-pages in that small shared 32-bit space. But such paging has a small performance impact (it is however much smaller than paging-in/paging-out to disk).

Today, everyone should use a 64-bit OS; it also has the advantage of extending the paging space on disk, so that even with just 4GB of physical RAM, you'll still get much more virtual 64-bit space usable for applications (paging I/O to disk is still faster than having to free memory in applications, by dropping precomputed data in order to regenerate it later).

A 64-bit OS also allows you to map giant files in memory using the memory manager, which is MUCH faster than conventional I/O (read/writes to files), because it saves a lot of overhead from the filesystem. This means that Windows can also start any application without having to read it completely in memory, it just maps the executable file in memory, and then the memory manager will load the pages only on demand: this considerably accelerates the application loat time, as well as the boot time, because most contents in the required files are not read completely, but only on-demand (on the first access.

Who wants to use XP today ? Go with a 64-bit OS. It is much faster !

Note: a 32-bit OS is still perfect if you run it within a VM as a guest OS, within a 64bit OS using an hypervisor; you get even better performance for this 32-bit OS today in such VM environment than what you got over a native 32-bit installation, because the 64-bit OS handles paging much faster, and virtualizes completely the filesystem to save lots of I/O performed by the hosted 32-bit OS.

XP 32-bit works still very well, as long as it is no longer the native OS, but only the guest OS running in a VM. Note that Windows 7 64-bit already supports running XP internally in a VM, but this built-in VM is a bit limited. There are other hypervisors that work much better and faster.

Comparing the performance of applications in an old native 32-bit XP installation and in a VM, I've found that the installation of XP only as a guest OS within a VM is MUCH faster today (at least as long as you don't need heavy graphics, but some hypervisors provide a builtin driver you can install in the guest virtual installation of XP, which works exactly like a standard driver for XP, but that will accelerate a lot the graphics rendering by forwarding these drawing using the graphics capabilities of the modern host 64-bit system. In that case you won't even see any deceleration, and in fact the graphics capabilities of the host will largely improve what was possible when using only a native 32-bit system (due to its memory adressing constraints). All I/O are in fact much faster than in a native 32-bit installation.

Games will work flawlessly (with even less troubles than when you were using antiquitated 32-bit graphics device drivers which were very insecure in many cases). And applications will even be more secure when running in a virtualized 32-bit installation of XP running within an hypervisor. There can even exist an excellent integration with the 64-bit desktop, including with shared files (with an additional very strong security offered by the VM isolation), a sharable (and secure) clipboard (allowing to communicate between the VM and its host, or between different VMs running in the same host.

Backups of XP are also much easier to do : the hypervisor provides that for you. Boot times of XP in a VM is also MUCH faster.

This means that your precious applications for XP do not have to be thrown away: upgrade the native OS, install the hypervisor, and reinstall XP as a guest within that VM (you can even reuse a complete system image of XP if you have one, to initialize your new VM).

Today, virtualization technologies now rock !

But I should have stipulated that the XP OS itself is designed to recognize 4Gb, but only reports less for other reasons similar to what you are talking about. I'm trying to keep it simple for the average reader here on CNET, but thanks for the post, as the average reader needs to know about application limits too.

and how did you do that?