You are looking an a Pentium 4M chip which is fine for gaming but keep in mind you will get very low battery life and high heat with it.
The ZX5000 series does have the option for the ATI 9600 video card with 128mb video dedicated graphics. If you want this than go for it.
Otherwise the Compaq X1000 and sister machine HPZT3000 (Pentium M) have the ATI 9200 video in 32mb or 64mb which is good for many games as well. But the more video memory you get the more games you will be able to play or at higher frame rates.
I have been very happy my X1360US (X1000 variant). You can read all the posts and HP discounts (Which would also apply to this laptop -- $100 rebate and $100 coupon) at x1000forums.com (10,000 registered users).
Toshiba is slightly better at reliability so look at Toshibas also but basically all the PC notebook manufacturers have similar reliability as they all are making the laptops overseas and they have similar components.
Apple is tops in reliability/service.
The only issues I had were taken care of by bios updates and driver updates on the HP/Compaq website.
Note, the X1000/ZT3000 weigh only 6.5 pounds with the same 15.4" widescreen and last 3.5 to 4 hours of battery life when using wi-fi. The Pentium 4M chip laptops will be much less.
You will get less battery life while playing intensive games that use the hard drive on all notebooks though.
The 1 major thing the HPZX5000 series has that the ZT3000/X1000 doesn't is the Briteview LCD screen option (in XGA). This is very nice and similar to Sony Xbrite or the new Toshiba Trubrite. It looks like a thin layer of glass over the LCD and it looks much sharper but some people don't like the reflection that gives off (and may be more of an issue outside). So see these screens at Circuit City, etc to decide on that.
If you decide you want a Pentium M laptop but also want the new screen technology look no further than the Toshiba M35S456 (retail 1999 with DVD burner and Trubrite but on sale for 150 off twice recently) -- this also has Nvidia 64mb dedicated video graphics and weighs 6.2 pounds.
note, if you do get a Pentium M cpu make sure you get a Dothan Pentium M at least 1.6mhz or higher as it has 2mb L2 system cache instead of the 1mb on the older Banias Pentium M's.
I'm looking to get a pretty top of the line gaming notebook for around 1500. the HP pavillion zx5000 has some nice customizable features and is relatively cheap . . . but I'm not too confident with the brand. Does anyone have any advice???

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