The Great Sephiroth

So there are some Asrock Dual (PCI-E + AGP) motherboards: 1. 4CoreDual-SATA2 (R2.0). 2. 4CoreDual-VSTA. 3. 775Dual-880Pro. 4. 775Dual-915GL. 5. 775Dual-915GV. 6. 775Dual-VSTA. 7. 939Dual-SATA2. 8. 939Dual-VSTA. 9. ALiveDual-eSATA2. 10. P4Dual-880Pro. 11. P4Dual-915GL. Due to the fact they have PCI-E + AGP they would be great for Windows 98/XP dual boot, but only 775Dual-880Pro and P4Dual-880Pro have official support for Windows 98(SE)/ME and drivers for those systems. But I keep reading that some other motherboards on this list are also valid for Windows 98(SE)/ME and can get this system and drivers installed. So how it is really? The most interesting and "powerful" motherboard on this list is ALiveDual-eSATA2 but I have no idea if you can get Windows 98(SE)/ME installed on this motherboard (or other AMD motherboard beginning with '939Dual' for that matter) and all drivers for this system without losing any important features. I've read somewhere that someone installed Windows 98(SE)/ME on ALiveDual-eSATA2 but I do not know if there were some sacrifices (if he lost important features due to missing drivers) or not. I do not want to lose important features for sure. It is top priority for me. I have to be sure. I won't go blindfolded for something I am not sure is compatible 100%. So I need confirmation. Has anyone got any experience with ALiveDual-eSATA2 and Windows 98(SE)/ME? Can I have all functionalities and don't miss any critical/important functions with this motherboard and Windows 98(SE)/ME? The 2nd most interesting motherboard group are 4CoreDuals and 775Dual-VSTA due to the fact they made possible to use Core2 series processors which may not boost much in terms of Windows 98(SE)/ME but may boost much in terms of Windows XP gaming. So it may be worth going for them in case of building Windows 98/XP dual boot PC. But they do not officially support Windows 98(SE)/ME. But many people report them working very well with Windows 98(SE)/ME. So what is the truth? Do they really work well with Windows 98(SE)/ME? Do they have 100% compatibility? Do we lose some functions? If yes, then which? I haven't found 100% clear info about this. But what I found that they have very similar chipset to 775Dual-880Pro (which 100% supports and works with Windows 98(SE)/ME). They have the same or almost the same northbridge (VIA® PT880 Pro/Ultra) but slightly different southbridge (775Dual-880Pro has VIA® VT8237R, 775Dual-VSTA and 4CoreDual-VSTA have VIA® VT8237A, 4CoreDual-SATA2 has VIA® VT8237S). Not sure what are the differences between those southbridges. I am not expert in this. But I found that VT8237A uses HD Audio instead of AC'97 and VT8237S in addition to this (using HD Audio instead of AC'97) also uses SATA-II instead of SATA-150. So it looks like on VT8237A (775Dual-VSTA and 4CoreDual-VSTA) we won't be able to use on-board sound (but I could live with that if PCI sound card would work) and on VT8237S in addition to not working on-board sound (but I could live with that if PCI sound card would work) also SATA(2) might not work under Windows 98(SE)/ME (but I could and I planned to use only IDE drives under that OS) because of lack of VIA chipsets drivers for that aspects under Windows 98(SE)/ME, if I am understanding/processing this correctly? But every other (VIA) aspects/functionalities and (VIA) drivers (like motherboard USB drivers, PCI slots, etc.) should work, if I am understanding/processing this correctly? Could someone confirm this or correct me if I am wrong? Does someone have any of those 4CoreDuals motherboards and/or 775Dual-VSTA motherboard and can confirm that there are not any more problems (than I mentioned) under Windows 98(SE)/ME and that this OS(es) works correctly/perfectly on this motherboards and can recommend those motherboards for this OS(es) or correct me and say that those motherboards are bad for those OS(es) and there will be more problems (than I mentioned) and tell me to not use them? I seeking/looking for 100% confirmation from someone who uses those motherboards because I don't want to buy dozen motherboards for testing purposes. I am sure people already know answers to all of this. I am looking for answer from someone who is familiar with those motherboards. The rest of motherboards I mentioned at the beginning seems less interesting.

You might be right. I read somewhere that those first PCI-E 2.0 cards (like 8800 GT) have different/worse PCI-E 2.0 implementation and can't fully go back to PCI-E gen 1. Later GPUs may have different/better PCI-E 2.0 implementation and may go down to gen 1. So I read. Would have to test this.

Unfortunately this won't work too. According to manufacturer only PCI-Express generation 1 GPUs work.

Unfortunately it won't work on this motherboard.

How powerful each line (3.3V, 5V and 12V) should be?

I am planning to build retro PC dual boot 98/XP on 775Dual-880Pro Asrock motherboard with Intel Pentium D 945 3.4GHz and 2 x 1GB DDR2 667MHz and GeForce 7950 GX2 or GeForce 8800 GTX/Ultra on PCI-E slot and another GPU on AGP slot (anything in the range GeForce4 Ti - 7950 GT), sound card on PCI slot, optical drive and floppy drive, probably 3 x 2.5 inch drives (1 2.5 inch SATA SSD connected to IDE using SATA to IDE adapter, 2 2.5 inch HDD IDE interface drives) and 2 x 3.5 inch HDD drives, maybe some card reader and maybe something on PCI in the future. What would be good PSU for this that has all the needed connectors and enough amps on all 3.3V, 5V and 12V lines? I have poor knowledge in this topic. Would Chieftec GPS-450AA-101A be good and have enough power? But even if it would be OK, is it wise getting this used PSU? Are used PSUs good idea? If not, are there any of new PSUs that would be good for this specific retro build? Would any of SilverStone Strider series PSUs be good for this specific retro build? If the mentioned 2 are bad, what PSU would you recommend for this specific retro build?