From Acer:

This package contains the 9.0.0.1011 version of the Intel ICH9 chipset installation utility for HP Computers running Windows Vista. It is highly recommended to always use the most recent driver version available. Tonymacx86.com: Home of the CustoMac Buyer’s Guide, iBoot, MultiBeast, UniBeast, and the world’s most helpful #hackintosh #mac #osx support community. Download drivers for Intel (R) ICH9 Family USB Universal Host Controller - 2937 chipset, or download DriverPack Solution software for automatic driver download and update. I have big problems if I choose the new ICH9 chipset for my guests. On the Windows 7 guest I get a BSOD after installing the guest additions. On the Windows XP guest there are yellow exclamation marks on every guest addition driver and the guest additions don't work at all.

Click on the following links for the driver package readme info:
Piix3

.../Chipset/Readme.txt
This package supports the following driver models:

Intel(R) 5000X Chipset Memory Controller Hub - 25C0
Intel(R) 5000Z Chipset Memory Controller Hub - 25D0
Intel(R) 5000V Chipset Memory Controller Hub - 25D4
Intel(R) 5000P Chipset Memory Controller Hub - 25D8
Intel(R) 5000 Series Chipset PCI Express x4 Port 2 - 25E2
Intel(R) 5000 Series Chipset PCI Express x4 Port 3 - 25E3
Intel(R) 5000 Series Chipset PCI Express x4 Port 4 - 25E4
Intel(R) 5000 Series Chipset PCI Express x4 Port 5 - 25E5
Intel(R) 5000 Series Chipset PCI Express x4 Port 6 - 25E6
Intel(R) 5000 Series Chipset PCI Express x4 Port 7 - 25E7
Intel(R) 5000 Series Chipset AMB Memory Mapped Registers - 25E8
Intel(R) 5000 Series Chipset Error Reporting Registers - 25F0
Intel(R) 5000 Series Chipset Reserved Registers - 25F1
Intel(R) 5000 Series Chipset Reserved Registers - 25F3
Intel(R) 5000 Series Chipset FBD Registers - 25F5
Intel(R) 5000 Series Chipset FBD Registers - 25F6
Intel(R) 5000 Series Chipset PCI Express x8 Port 2-3 - 25F7
Intel(R) 5000 Series Chipset PCI Express x8 Port 4-5 - 25F8
Intel(R) 5000 Series Chipset PCI Express x8 Port 6-7 - 25F9
Intel(R) 5000X Chipset PCI Express x16 Port 4-7 - 25FA
Intel(R) 6311ESB/6321ESB PCI Express Upstream Port - 3500
Intel(R) 6310ESB PCI Express Upstream Port - 3501
Intel(R) 6311ESB/6321ESB I/OxAPIC Interrupt Controller - 3504
Intel(R) 6310ESB I/OxAPIC Interrupt Controller - 3505
Intel(R) 6311ESB/6321ESB PCI Express to PCI-X Bridge - 350C
Intel(R) 6310ESB PCI Express to PCI-X Bridge - 350D
Intel(R) 6311ESB/6321ESB PCI Express Downstream Port E1 - 3510
Intel(R) 6310ESB PCI Express Downstream Port E1 - 3511
Intel(R) 6311ESB/6321ESB PCI Express Downstream Port E2 - 3514
Intel(R) 6310ESB PCI Express Downstream Port E2 - 3515
Intel(R) 6311ESB/6321ESB PCI Express Downstream Port E3 - 3518
Intel(R) 6310ESB PCI Express Downstream Port E3 - 3519
Intel(R) 631xESB/6321ESB/3100 Chipset LPC Interface Controller - 2670
Intel(R) 631xESB/6321ESB/3100 Chipset SMBus Controller - 269B
Intel(R) 631xESB/6321ESB/3100 Chipset PCI Express Root Port 1 - 2690
Intel(R) 631xESB/6321ESB/3100 Chipset PCI Express Root Port 2 - 2692
Intel(R) 631xESB/6321ESB/3100 Chipset PCI Express Root Port 3 - 2694
Intel(R) 631xESB/6321ESB/3100 Chipset PCI Express Root Port 4 - 2696
Intel(R) 82852/82855 GM/GME/PM/GMV to Processor I/O Controller - 3580
Intel(R) 82852/82855 GM/GME/PM/GMV to Processor I/O Controller - 3584
Intel(R) 82852/82855 GM/GME/PM/GMV to Processor I/O Controller - 3585
Intel(R) 82852/82855 GM/GME/PM/GMV Processor to AGP Controller - 3581
Intel(R) 82855PM Processor to I/O Controller - 3340
Intel(R) 82855PM Processor to AGP Controller - 3341
Intel(R) 82865G/PE/P/GV/82848P Processor to I/O Controller - 2570
Intel(R) 82865G/PE/P/GV/82848P Processor to AGP Controller - 2571
Intel(R) 82865G/PE/P/GV/82848P Processor to PCI to CSA bridge - 2573
Intel(R) 82865G/PE/P/GV/82848P Processor to I/O Memory Interface - 2576
Intel(R) 82875P/E7210 Memory Controller Hub - 2578
Intel(R) 82875P Processor to AGP Controller - 2579
Intel(R) 82875P/E7210 Processor to PCI to CSA bridge - 257B
Intel(R) 82875P/E7210 Processor to I/O Memory Interface - 257E
Intel(R) 915G/P/GV/GL/PL/910GE/GL Processor to I/O Controller - 2580
Intel(R) 915G/P/GV/GL/PL/910GE/GL PCI Express Root Port - 2581
Intel(R) 925X/XE Memory Controller Hub - 2584
Intel(R) 925X/XE PCI Express Root Port - 2585
Mobile Intel(R) 915GM/PM/GMS/910GML Express Processor to DRAM Controller - 2590
Mobile Intel(R) 915GM/PM Express PCI Express Root Port - 2591
Intel(R) 945G/GZ/P/PL Processor to I/O Controller - 2770
Intel(R) 945G/GZ/P/PL PCI Express Root Port - 2771
Intel(R) 955X Memory Controller Hub - 2774
Intel(R) 955X PCI Express Root Port - 2775
Intel(R) 975X Memory Controller Hub - 277C
Intel(R) 975X/3010 PCI Express Root Port - 277A
Intel(R) 975X PCI Express Root Port - 277D
Mobile Intel(R) 945GM/PM/GMS/940GML/943GML and Intel(R) 945GT Express Processor to DRAM Controller - 27A0
Mobile Intel(R) 945GM/PM/GMS/940GML/943GML and Intel(R) 945GT Express PCI Express Root Port - 27A1
Intel(R) 946GZ/PL/GL Processor to I/O Controller - 2970
Intel(R) 946GZ/PL/GL PCI Express Root Port - 2971
Intel(R) Processor to I/O Controller - 2980
Intel(R) PCI Express Root Port - 2981
Intel(R) Q963/Q965 Processor to I/O Controller - 2990
Intel(R) Q963/Q965 PCI Express Root Port - 2991
Intel(R) P965/G965 Processor to I/O Controller - 29A0
Intel(R) P965/G965 PCI Express Root Port - 29A1
Mobile Intel(R) PM965/GM965/GL960 Express Processor to DRAM Controller - 2A00
Mobile Intel(R) PM965/GM965/GL960 Express PCI Express Root Port - 2A01
High Precision Event Timer
Intel(R) 82801 PCI Bridge - 244E
Intel(R) 82801 PCI Bridge - 2448
Intel(R) 6702PXH PCI Express-to-PCI Bridge A - 032C
Intel(R) E7220/E7221 Memory Controller Hub - 2588
Intel(R) E7220/E7221 PCI Express Root Port - 2589
Intel(R) E7230/3000/3010 Processor to I/O Controller - 2778
Intel(R) E7230/3000/3010 PCI Express Root Port - 2779
Intel(R) E7520 Memory Controller Hub - 3590
Intel(R) E7525/E7520 Error Reporting Registers - 3591
Intel(R) E7320 Memory Controller Hub - 3592
Intel(R) E7320 Error Reporting Registers - 3593
Intel(R) E7520 DMA Controller - 3594
Intel(R) E7525/E7520/E7320 PCI Express Root Port A0 - 3595
Intel(R) E7525/E7520/E7320 PCI Express Root Port A1 - 3596
Intel(R) E7525/E7520 PCI Express Root Port B0 - 3597
Intel(R) E7520 PCI Express Root Port B1 - 3598
Intel(R) E7520 PCI Express Root Port C0 - 3599
Intel(R) E7520 PCI Express Root Port C1 - 359A
Intel(R) E7525/E7520/E7320 Extended Configuration Registers - 359B
Intel(R) E7525 Memory Controller Hub - 359E
Intel(R) 6700/6702PXH I/OxAPIC Interrupt Controller A - 0326
Intel(R) 6700PXH I/OxAPIC Interrupt Controller B - 0327
Intel(R) 6700PXH PCI Express-to-PCI Bridge A - 0329
Intel(R) 6700PXH PCI Express-to-PCI Bridge B - 032A
Intel(R) 80332 PCI Express-to-PCI Bridge A - 0330
Intel(R) 80332 I/OxAPIC Interrupt Controller A - 0331
Intel(R) 80332 PCI Express-to-PCI Bridge B - 0332
Intel(R) 80332 I/OxAPIC Interrupt Controller B - 0333
Intel(R) 80332 Memory Controller - 0334
Intel(R) 80333 PCI Express-to-PCI Bridge A - 0370
Intel(R) 80333 I/OxAPIC Interrupt Controller A - 0371
Intel(R) 80333 PCI Express-to-PCI Bridge B - 0372
Intel(R) 80333 I/OxAPIC Interrupt Controller B - 0373
Intel(R) 80333 Memory Controller - 0374
Intel(R) E8500/E8501 Hub Interface - 2600
Intel(R) E8500/E8501 PCI Express x4 Port D - 2601
Intel(R) E8500/E8501 PCI Express x4 Port C0 - 2602
Intel(R) E8500/E8501 PCI Express x4 Port C1 - 2603
Intel(R) E8500/E8501 PCI Express x4 Port B0 - 2604
Intel(R) E8500/E8501 PCI Express x4 Port B1 - 2605
Intel(R) E

Ich9 Chipset Driver For Mac