Another answer (sorry - too long for the comment box):
Well, I'm a bit stumped. To clear something up, you say you were 'deleting' avast? do you mean you were uninstalling it, from Control Panel>Programs and Features? I hope so!
As for why you were unable to uninstall it a second time, I have no idea, but that's worrying.
Cached physical memory is data from RAM that has been stored in the swap file (or page file), which is a reserved area on the hard drive. This happens when the RAM becomes full, but the information it holds will be needed again. The fact that the RAM is becoming full upon startup is worrying, because it shouldn't! Windows will automatically manage the page file size, although you can manually set it. Don't bother changing anything to do with this - it's a symptom, not a cause.
My only suggestion at this point would be to reinstall Windows afresh, all over again, this time installing drivers first, and in the correct order.
Download them here: http://h20564.www2.hp.com/hpsc/swd/publi...
In the order they appear on the site, download
- BIOS (ROM Firmware for blah blah (International)
- Software - System management>BIOS Configuration Utility
Download each driver to its own folder, and name the folder. Often, driver setup files aren't clearly named after what they actually are.
Omit any I haven't mentioned - you won't need them (unless you use the dial up modem). Store the downloaded files on a USB stick or CD.
Save any personal files you want to keep, as the drive will be wiped.
Reinstall Windows afresh, and leave out your network cable (if you use one). At the drive options screen during installation, delete all partitions, and just click next - Windows will do the rest.
When Windows boots for the first time, DON'T connect to the internet - we don't want any wrongly identified hardware, and therefore incorrect drivers, so no ethernet, and no Wi-Fi (if you have it).
I REPEAT - REMOVE THE NETWORK CABLE, AND DO NOT CONNECT WI-FI!
First thing to do is create a System Restore point that we can revert back to if anything goes wrong.
To create a restore point:
- Open System by clicking the Start button, right-clicking Computer, and then clicking Properties.
- In the left pane, click System protection.
- Click the System Protection tab, and then click Create.
- In the System Protection dialog box, type a description, and then click Create.
Insert the USB or disk with the drivers, and copy them all to your you hard disk - your desktop, if you like.
Run the installers from the location you copied them to, not directly from the USB stick or CD/DVD.
Install the drivers in this order:
Now, we MIGHT not need the BIOS configuration utility, as the actual BIOS firmware seems to come as an .exe, which means you should just be able to run it. BIOS is the low level firmware that runs when the computer turns on, and having it up to date is often vital to the operation of many aspects of the computer.
Run the BIOS (ROM Firmware for blah blah (International) .exe file.
During the BIOS flashing process (flashing means writing the firmware to the BIOS chip), DO NOT QUIT THE PROGRAM, AND DO NOT TURN OFF THE COMPUTER! If you do, the motherboard will probably be useless. Don't be deterred, though - do go ahead with this, as the current BIOS is only from last year. Not bad for a five year old machine. Anyway, the BIOS flash should take no more than five minutes, and the computer should restart itself when done. When it does, you might see unusual behaviour, as the BIOS will complain that settings have changed. Just press the key it says to continue - usually F1, or F2.
After all that, check how the system resources are doing. Any improvement? Still ok? If so, connect to the internet. If you need to install a Wi-Fi adaptor driver, do that now.
Go Control Panel>Windows Update, and let Windows download all the updates it can find. This will take a LOOOONG time for Windows 7. I installed Windows 7 from disk for someone last week, and all the updates took over a day. It was looking for the first lot of updates for over four hours, before it came back, so be prepared to leave your machine overnight while it searches. Ok the updates (in the morning, probably!), and let them install. Just to be safe, don't use the machine while it's doing these updates - leave it alone. You will need to approve a load of multiple updates, multiple times, so be patient.
When Windows finally says that there are no more updates, review your system performance. How is it? If ok, good! At this point, create another System Restore Point.
Then attempt to install the latest version of Avast.