Is it possible to fit a Intel Pentium(R) D 840, 3.2 GHz Processor (Dual-Core)?

and a nVidia GeForce 7300LE Graphics Card to a HI-GRADE Winputer PV4 2600A desktop?

Is it possible to fit a Intel Pentium(R) D 840, 3.2 GHz Processor (Dual-Core)?

As long as the motherboard they are using supports it, next yes. You might open up the computer, and look for any model numbers or brand name on the motherboard and do a search for that on Yahoo and see if you can grasp specs on the Mobo. Otherwise, call the company that made it and ask them.
Have a loook here, you will requirement Adobe Acrobat reader to view though, hope this help.



http://www.higrade.com/media/other_docum...
Yes, BUT you may have to UPGRADE power supply. It looks approaching you have a teeny weeny 250 watter contained by there. Now, the processor you are considering is a 130 watter while your existing one could be an 84 watter. You will also be calculation a 24 watt graphics card. I believe you need at least possible a 350W Power Supply, but a 400W would run cooler and provide you with elbow room for adjectives upgrades.
after researching your p.c i can tell you its possible to upgrade both of these components,the pentium d 840 should fit ok as its a socket 775 processor comatible next to your current motherboard

with regard to your graphics,the nvidia geforce 7300le is avalible in a.g.p form which your p.c requires

may i recomemend the geforce 7300gt(http://www.scan.co.uk/products/productin... is a similar card but slightly more powerful than the 7300le,again this is a agp text

for a datasheet on your current p.c look at...http://www.higrade.com/media/other_docum...

well done on a excellent choice of upgrades

biddable luck mate!