Reboot Loop with HP desktop computer Presario SR1308OM

I have an HP desktop computer Presario SR1308OM with 1GB of Ram 32-bit ADM Athlon 64 Processor 3200+ 2.21 GHz. Installed Win Vista Business last month after formatting the drive.  Before installing Win Vista Business last month, it had been running Win XP for years. Two months ag it startsed rebooting by itself occasionally,then it got into a rebooting loop. I took it into a tech and he said the registry was trashed & I had to reinstall XP. I went ahead and installed Win Vista Business, since I already had prchased a copy.  Now, the rebooting has started again. Occasionally at first, now it will reboot if I try to print from Adobe Reader X, or click on a link in IE. If I try to boot into Safe Mode, it reads all the files then reboots before it ever gets into Windows.
I have been getting a lot of "High Memory Usage' warnings in Vista & in XP.
If it has to do with Ram, I incidentally ordered 2GB of Ram from Crucial that is in the mail now.  Any way to determine what is causing the rebooting & how or if it can be fixed?
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If you go to properties of the Computer, then the Advanced Tab, then click Settings under Startup and Recovery, you can uncheck "Automatically Restart".  This should make it so the system stays on the blue error screen next time it crashes, and you might be able to determine the cause of the reboots.
you should enable memory dump and you can try looking at the memory dump files , that will tell what causing it to reboot .

please check my article at

It can be that your memory is becoming faulty. You can test this with memtest 86 (you can get it here )

Run the test at least 3 times to be sure that the memory is OK.

It can also be dust in computer. To remove this dust, open the cabinet and use compressed air to blow the dust away.

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to be sure, i recommend ram and disk diags- best download ubcd to run them :      
Just as another precaution, open the pc and look at the motherboard closely and make sure that none of your capacitors on the board are domed; they should all be flat.  If you see one that is domed, then that may be your problem.  Also, if all is ok with the board, remove one memory stick and try to run it that way, see if that elliminates your problem, do this with both sticks, swap slots, you find your answer there if one of your sticks or memory slots are bad.  Last, you may want to run a disk check, and make sure your HDD does not have any bad sectors; I know we all want to believe its an OS problem at first; but doing a physical check also eliminates reinventing the wheel.
gocallaAuthor Commented:
Thanks everyone!

I'm going to install the 2 new 1GB memory cards today and see if that solves the problem and then get back to you.
why don't you test the old ones as suggested??  that will show if there are problems..
gocallaAuthor Commented:
No reboots after installing new memory.
gocallaAuthor Commented:
Great help
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Windows Vista

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