754 socket with PCI-E

johnnyrebb

Junior Member
Jun 26, 2005
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hello all
ive been tryn to piece a new rig. have my eye on the 3700 alrdy got a x800xl.

now im just tryn to find some 754 socket boards with pci-e instead of agp.

need some help with some choices here. all ive gotten so far is the asus k8n4-e deluxe

and an msi board. Asus been favored but ive heard a bad review on the onboard fan

they are using. anyone has additional info plz advise.
 

Peter

Elite Member
Oct 15, 1999
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ECS NForce4-A754, the lookalike twin of their -A939.
The 754 Athlon3700 is about $100 more than the 3400 which runs at the same 2.4 GHz. These $100 are much better invested elsewhere than a larger L2 cache.
 

Peter

Elite Member
Oct 15, 1999
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The AGP slot on those (like on all others that do this*) is a fake. This is PCI signalling at PCI speeds and - most importantly - at PCI voltage levels. Only those older AGP cards that happen to be backward compatible to 2x/1x AGP or PCI signalling even work in there, and even if they do, performance is ridiculous.
Dangerous and stupid: All those manufacturers use an AGP slot keyed to pretend 1.5V signalling (4x/8x modes) but actually do 3.3V signalling. Card barbecue!

* Except those that use the ULi 1695/1567 chipset, or an NForce4pro paired with an AMD8151.
 

Zap

Elite Member
Oct 13, 1999
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Originally posted by: Peter
The AGP slot on those (like on all others that do this*) is a fake. This is PCI signalling at PCI speeds and - most importantly - at PCI voltage levels.

I read somewhere that MSI stated they were using a PCI-E lane for the AGR slot, not a PCI slot for that motherboard. Anyone have more info on this?
 

Peter

Elite Member
Oct 15, 1999
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Since there are no PCIE-to-AGP bridge chips to be had AT ALL (for the uniqueness of AGP's mechanisms, this is impossible anyway), only PCIE-to-PCI. You'd again be back to 3.3V signalling which is plain unusable for recent AGP cards.

See whether you can spot a PLXtech 8111 chip on such a board ... I doubt you will. You will rather find that a lot of traces run straight from the PCI slots to that not-really-AGP slot. Guess why. You may also take a guess at why their list of compatible cards has nothing but older stuff (which still does 3.3V signalling for 1x/2x AGP modes).

There are few ways to do it properly:

* ULi M1695+M1597 chipset, the only chipset out there with PCIE 16x _and_ proper AGP.
* P4 owners would have to do with VIA (PT890pro?): PCIE4x and real AGP.
* For AMD64 platform, there's AMD's own Hypertransport-AGP tunnel chip still to be had - combine with any PCIE chipset.
* Or combine the ULi M1695 with any old AGP chipset for AMD64, like ULi themselves do.

None of these options are cheap though.