Hi,
From the HP support site:
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Memory slots: 4 DIMMS
- Maximum memory:
- 8 GB (4 x 2 GB) (64-bit OS)
- 4 GB* (4 x 1 GB) (32-bit OS)
*Actual available memory may be less
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Excerpted from the Product Specifications Guide, link available here:
HP Pavilion Elite m9300t Product Specifications and Configurable Options | HP® Customer Support It's worth noting that even though your PC will take 8GB total RAM with 4 sticks of 2GB RAM; you still can't access it all unless your processor chip is a 64bit CPU *which yours appears to be*, AND you are running a 64bit version of Windows (Vista-W10) as well.
There are 4 possible Quad Processors that your model might have, so you'd have to run a diagnostic program such as
SPECCY to determine exactly which flavor you have:
**again excerpted from your Product Specifications Guide above; here are the 4 possibilities:
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Core 2 Quad Q6600 (K) (2.4GHz /1066 MHz) 8 MB L2 cache; Quad Core
- Core 2 Quad Q6700 (K) (2.66GHz /1066 MHz) 2 x 4 MB L2 cache; Quad Core
- Core 2 Quad Q9300 (Y) (2.5GHz /1333 MHz) 6 MB L2 cache; Duo Core (95W)
- Core 2 Quad Q9450 (Y) (2.66GHz /1333 MHz) 12 MB L2 cache; Duo Core (95W)
- ---------------------------------------------------------------------------------------------------------------
- It appears that all of these Quad-Core CPUs that any one of these might be inside your current PC are all 64bit processor chips; which is good, in that if you are running a 64bit Windows version as I mention, you could access most if not all of 8GB RAM if you decided to upgrade your PC. You listed your question on the Windows7 forum, so I'm guessing you upgraded your PC from Vista which it came with several years ago. The next question you have to find an answer to is what EXACTLY is your Windows7 version? There are 9 possibilities; but for just Home Users, it's usually Win7 Starter(32bit), Win7 Basic(32bit), Win7 Home(32bit), Win7 Pro(64bit), or Win7 Ultimate (64bit).
If you have one of the 32bit flavors of Win7, it is possible to upgrade to one of the 64bit version, but that will require a complete OS reinstall on your PC, best done by a licensed Computer Pro. Since you state you can't do the work with your hands, it would be best to pay a Tech to open your PC, test it, and install the RAM and even buy it from the Tech if he works in a retail computer store. Then he can upgrade your Win7 to 64bit, and you'd be good to go then with the max RAM your PC can handle, 8GB.
You can expect this whole thing, labor and parts to run about
$180-$200 US or so at most computer stores or independent Techs. This is a lot of money to invest in a PC that's going to be 9 years old this year (your PC built in 2008), and only has 1 year of life left in it.
PCs other than Dell won't last more than 10 years in the majority of cases.
Your PC is teetering on the edge of obsolescence! Of course it's your computer; but for that kind of investment, you can buy a brand new Dell laptop for right around $200 on sale or a Chromebook. If you are not doing online gaming, either of those might make more sense.
Hope this answers your question.
Best of luck,
<<<<BIGBEARJEDI>>>> 
If you are confused by all of this, the short answer is you CAN add the extra 4GB RAM memory to your PC, but 
