This problem started just last night and I've gone through a series of possibilities, and I'm pretty sure I've ruled out it being the Video Card, at this point I'm assuming it is the Hard Drive, but I wanted to get an opinion that has actual value rather than my own >.<

Last night I shut down my computer via start menu and went to turn it back on and when I did the screen went blank/black after the "boot menu" (not 100% sure what that menu is called, its where its kind of blue (i have an hp) and you can hit Esc, F9, F10, F11). After that happened I figured oh well maybe it just loaded wrong, so I shut it off, now when I hit the power button, rather than having to hold it down, I just press it once even lightly and it just shuts down completely. Normally when you hit it you have to hold it down to shut it down completely (or so I think).

Now I'm currently using an 'Nvidia GeForce GTX 260' video card, I swapped that out with a working one which was an 'Nvidia GeForce GT 520', not 100% sure if the 2 were compatible or not, but it fit and everything ok. Computer still did the same thing with the other video card. I didn't try the current one (in the broken computer) in the working computer, to rule it out completely. I just assuming that was the cast, besides it wouldn't fit in the other computer, or didn't have some of the cords.

Which is why I came to the assumption it is the Hard Drive, A; (as google puts it) Logical Hard Drive Failure. I'm not really sure what that is, seems like it can happen due to a virus, deleting system files, etc... I'm also not sure on what to look for if one occurs, can the screen load that boot menu and actually go blank afterwards (like when its loading windows)?

Anyways, I have no clue where to go from here or what steps to even take.

If needed, here are my system specs;
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Intel Core i7-920 Processor
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9GB DDR3 System Memory
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1 TB Hard Drive (Made by Seagate it looks like) (I'm pretty sure there are 2 drives aswell, a much smaller one that stores most of the system files and the giant one, though I see nothing inside the actual computer that would indicate a 2nd drive)
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Nvidia GeForce GTX 260 with 1.8 GB Dedicated Graphics Memory
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Annnnnd....Windows 7

Incase anyone was also curious the video card I tested with was;
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GeForce GT 520 with 1024 MB DDR3


The computer itself (that I use and am currently experiencing problems with) is HP Pavilion Elite HPE 170f PC.

How do you get 9GB of system memory?

I have 6 slots for memory

I apologize I'm not really very tech savvy, I know a little bit.

By me downloading that Hiren's BootCD, do I then (from another computer obviously) put it onto a disc then put it in my bad computer and it'll load or something?

Also I do not have a windows 7 dvd, do you know where I may be able to purchase one, or how much they might cost me?

Update - So you can close this topic.

I fixed my problem, was a hard drive issue. Didn't pinpoint the problem, but basically borrowed a friends Windows 7 DVD, reinstalled. Since when you overwrite an existing Windows OS and saves all your files in a "Windows.old" folder, I just brought up the command prompt and loaded all the files and folders where they needed to be via Recovery Menu (on Windows 7 Disc from Boot-up, not desktop).

Anyone with similar problems hope this helps.