Remember in my reply #10 I advised;
It seems that Acer machine will work for me even though it has only 300w vs 480w for the IBuyPower.
Most bundle providers use poor quality power supplies to keep costs down, this can cause damage to your other hardware but it is often only realized when the system is out of warranty.
As the Acer is using onboard graphics it does not need a more powerful power supply, the computer as it is will do everything that you require of it, if you wished to fit an add on video card you would also need to add a better power supply, for the same reasons that I stated earlier I would do the same if adding a new video card to the IBuyPower computer as you have no way of knowing the quality of the 480W PSU, this is not an unusual occurrence by the way.
Also, it has a VGA connector vs DVI. My current monitor has VGA, but what will happen in the future? I have read somewhere that DVI is the future. Is this correct? Is there an adapter if I'll get a DVI monitor? and all together what is better?
The newer displays made today have DVI and HDMI ports, DVI is the present norm but over time it will be replaced and possibly by HDMI.
Yes you can purchase a VGA to DVI port adapter (see .jpeg below) and DVI is deemed an improvement over VGA when connected DVI to DVI port, on a side note I once used such an adapter and enjoyed many years of demanding gaming without any issue.
The information is not available at Newegg so I will look on the Acer website for the details, for now to help you with this read the specs and the information at the Newegg feedback tab, for what it is worth the video card in the IBuyPower computer costs around $50.
i could not figure out what is Aser's video card memory speed?
If me I would purchase the Acer as it meets the required needs, is a proven brand and it could be easily upgraded in the future should you wish to, for your intended use I do not see this as being necessary.
Sorry no not without making the improvements I suggested or reinstalling XP, the computer is simply not powerful enough for Windows 7, you could try a lower screen resolution and make sure that the Windows 7 aero feature is turned off, to turn off aero, Right click on the Desktop - Click Personalize - Under 'Basic and High Contrast Themes, click 'Windows 7 Basic' and you are done.
Meanwhile, is there a way to figure out and fix the original problem without upgrading my current machine?