Well, it depends where you live. If it's US dollars you are talking about, you can easily buy a nice Radeon 9600 Pro for much less than $150. If it's Canadian $150, I'm not sure. I'd guess a GF4Ti4200 or Radeon 9600 Non-pro are your best bets then.
At Newegg.com, they have an oem Saphire for $139, or a Gigabyte retail box for $140. DO NOT buy the powercolor EZ version clocked 400/400, it is much slower and costs almost as much. I'd avoid GeCube also.
If you can push your limit a tad, for $149-$152 you can find a Transcend or Gigabyte Radeon 9600XT. You DO NOT get HL2 with these two cards, you have to spend at least $160+ to find one with HL2. The 5900XT if found in stock for $159 is a powerful card for the money if you want NV.
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ABIT IS7, P4 2.6C, 512MB Corsair TwinX PC3200LL, Radeon 9800 Pro, Santa Cruz, TruePower 430watt