HyperDroidGBX (Gingerbread Xtreme Edition) is the first open-source custom ROM designed and optimized just for HTC HD2. It is cooked by XDA Developer, pongster. I was staying away from his builds all the while because of LCD Density at 167 by default. For me, all the stuffs are way too small on this density. So I changed it back to 240. By the way, this ROM is based on Android 2.3.3 Gingerbread and using Tytung r8.3 Kernel.
Make sure that you change ro.sf.lcd_density=167 to 240 at build.prop (system folder) before you install the ROM if you want normal screen density.
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Download HyperDroidGBX v11 [Kernel: Tytung r8.3] NAND A2SD+ Zip ROM here.