I started to notice this probelm when I bought an OEM keyboard. My PC concepts Keyboard with built in touchpad lasted me 2 years, and played very nice. I had thought I lost my ability to strafe jump over the years.
finally I heard about the Z-board being able to read 8 keystrokes at once, and so I started looking for keyboard with this in mind. The Z-board gets expensive, and I didn't want a special keypad for gaming, that I coudln't use for typing.
December, I got the Saitek Eclipse and I've been super happy I know I can press 5 keys at once and it works fine, you just cant press asdfgh at the same time. I use the WASD pattern to move, with space for jump, R to select rockets, z for zoom, x for scripts, f for grappling hook, g for taunt, etc..... (I play alot of Q3). This keyboard is back lit, and they keys are laser Etched so the lights shine right through. I resisted buying it on the neatness factor, but looked at it a few times, and read some reviews.
The keyboard is very smooth, the keys are very responsive, the keyboard has some weight to it, plus larger rubber feet on the corners to help hold the keyboard in place. Saitek has been in business since 1977 making various hardware devices such as gaming controllers. You can google and read a couple reviews on teh keyboard. Stop by your local Circuit City to try it out. BestBuy had it on sale for $40 last week.
Google for reviews
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