Help with my computer! Low performance.

[Raist]

http://www.videocardbenchmark.net/vi...GeForce+GT+420

Scored an average of 442 on their list (slower than Intel HD 4600 on-board graphics). Want to be scoring at least in the 700-750 range to stand a change of consistently hitting 25FPS or better. When looking at your options, you can browse their lists or use their search engine (just plug in the number and it will suggest cards it has in it's list: type 640 and it will list different ones, click the GT640 to see it's stats):

http://www.videocardbenchmark.net/index.php

Specs for the OEM card, Retail may be a bit better:
http://www.nvidia.com/object/product...20-oem-us.html

You may not always see the GB/sec rating right away when looking at a card, but you should always see some details on the memory. If in a store flip the box over, or look along the side of the box--all the specs should be listed somewhere. One rule of thumb I always shoot for is avoiding the 128bit versions. At least the bit rate and the format of the memory will be right on the front of the box (128-bit DDR3). 128-bit is sort of a red flag for the budget level cards, and often there really isn't much of a premium to move to 256bit (more bits in the pipeline means more bytes passed per clock cycle--it's a cheap way to enhance throughput). The exception though may be if you are looking at lower DDR types though in combination with a higher bit (DDR2 versus DDR5, and there are also GDDR formats too). Basically, you need to be aware of the memory formats in use if you can't find an actual GB/sec memory bandwidth listed. Ideally, a 256bit DDR5 option is what I look for, but sometimes it may not fall in the price range one is looking for.