Hi guys!

I have the following 3dfx cards:

Diamond Voodoo2
Creative Voodoo Banshee

And i've just purchased a voodoo5 5500 AGP on ebay

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3684090503

I have a question tho you may solve, what are the advantadges of a V5 agp versus a PCI one, is there any?
I saw in a voodoo5 faq the card doesnt use system memory for textures via AGP features, so is there any advantadge of having a V5 agP?

Thanks for reading

Sergi

You can use the V5 PCI in the newest mainboards but not the AGP version because it only supports 3,3V.
If you have many PCI cards in your system the AGP will be faster.

Thats not a problem for me as I'm using an "old" mainboard that *only* supports AGP 3.3v
My system is:
Soltek mobo, (via chipset)
PIII 866mhz
320 mbytes of pc-133 SDRAM

I'm currently using 2 PCI cards only, the soundcard (SB Live! player 5.1) and the NIC

So thats the only advantadge of using a V5 agp vs a PCI one?

Postdata: Sergi = grunw = me (didnt have cookies enabled)

@grunw,

I have both a 5500 agp & pci, the performance difference is marginal at best, through testing on the same system (xp2400+) I have found the agp to be just slighty faster "just". You can get slighty more performance also with a agp version if you'r overclocking your processor and the agp bus speed gets increased, mine is at 83 mhz versus the standard 66 mhz.

The only real difference between the agp and pci versions are the differences in the bus speeds (pci = 33 mhz versus agp = 66 mhz)

Hope this helps

Thanks for your replies to Fish and Voodoo5500.
If any1 wants to add more info about it, i will be pleased to read.

Sergi

Voodoo5 PCI is PCI66 device, so it runs at 66MHz on PCI 2.2 motherboard.

???

So.. I guess making the AGP versions of cards was a pure marketing issue for 3dfx..

Same way as PCI-eXpress is now a marketing strategy for ATi/nVidia/whoever.

I mean, the speed of the bus itself only affects data transaction,
now, when was the last time that you've seen a performance increase when going from AGP1x to even AGP8x?
Or when using fastwrites?

Truth is never, gfx cards nowdays almost never do swapping anyway, they don't need those high speed buses.
Heck, the Hercules 3D Prophet 8500 64mb that I have, doesn't even swap in DeusEx2, and in high details - that game would even make your 9800pro beg for mercy.
So anything above AGP1x is pure marketing hype.

I mean, 10gbit ethernet might need PCI-eXpress, uh.. 50 megapixel video cameras might need PCI-eXpress, maybe even some extremely-high-end sound cards.
But video cards? pft

well for whatever reason my agp 5500's have been more than 10% faster than my pci 5500, have no idea why but that is some difference, otherwise i'd just use my 5500 pci in a newer board

Well, since all Voodoo4/5's only effectively communicate over 33MHz 32bit PCI Bus (never seen any of my Motherboards actually activate the PCI66 option), it is half the speed of the 66MHz 1xAGP version and a quarter of the 2xAGP version.

Since that's only valid for actual Transfers via the AGP Bus, and the Command FIFO not using it excessively, the ~10% (can be almost 0% in other applications) advantage is normal.

Newer Games (e.g. UT2003) should make the biggest difference, as they swamp the Bus with T&L Data for the Cards to render.

There was a benchmark at Tom's site a pretty long while ago when AGP8x cards were introduced.

You know what? when going from 1x to 8x the **best** increase he got was just about 2% :)

Well, that's Tom as we know it ;)

Anyway, it largely depends on the Application you throw at it.

I mean, run Unreal Tournament on 2x/4xAGP vs. 8xAGP Cards, and you'll see those 1-2% (at best).

Do the same using the (extreme by all means) CodeCreatures benchmark, and you can see upto 60% in isolated Cases.

The trick is to force the Card into AGP Texturing, that's it.

But still, the usefulness of 8x AGP is (today) mainly limited to getting T&L data and other misc. stuff over the Bus to the Card quick.
AGP Texturing is really not used alot (if at all), since it drops performance way too low.

But if you want to see 8x AGP at it's best, use a 64MB Card, set it to 2xAGP and run UT2003 in maximum Texture Detail (requires manual Engine flush to enable true 256MB Textures); 128MB (default maximum) should so as well however.
Then, repeat procedure on 8xAGP.

(Problem here is finding a 8xAGP capable Card that actually still supports 2xAGP)

----------------
The difference from 4xAGP to 8xAGP in turn, is neglectable, simply because 4xAGP already almost exceeds most system's total available "spare" RAM bandwidth (which is naturally shared among other Tasks, e.g. PCI Bus & CPU).
So 8xAGP would just bottleneck the RAM even more, yielding either no reasonable performance increase (worst case), or still less than expected...

It's just hard to find the right combination of Cards and Applications that posess enough Textures to force AGP Texturing, and provide a Platform that can spare sufficient RAM bandwidth for the 8xAGP to actually use as advantage over 4xAGP.
-----------
But by all practical means, I agree :
We don't really need 8x AGP as of now.
And when the time comes we could actually need it, we'll find the performance drop being probably too significant to be useful.

Well i can imagine a system with a P4 EE, and 2 gigs of Dual DDR 4500 wouldn't bottleneck the AGP bus.

I can actually think of a card with both 1x and 8x - the Radeon 9200, a remake of 9000 but with agp8x support.

In all due seriousness, I don't think that going from 2x to 8x would actually yeild 60% faster performance - doesn't matter where.

However, i do think that the infamous Bill Gates quote "640k is more than enough for anyone" applies here - we have the technology, we just don't have anything that can efficently take advantage of it

Even that System could bottleneck it enough to reduce 8xAGP efficiency, trust me ;)

The basic Problem is :
Applications that ship sufficient Textures to overload modern 128MB Cards (and potentially show the use or limitations of AGP Texturing) usually are very CPU intensive as well, and cause a very high Memory bandwidth demand all by itself already.

A P4EE with 2Gigs of RAM is already limiting itself, since it's forced into using slow PAE, which causes all P4's to take a notable hit (can lose upto 30% performance by that alone)

With a completely synthetic, pure AGP Texturing benchmark, one could even achieve much higher difference in scores, but so far I've never seen one.
(not very useful in general anyway, that's probably the reason none exists)

word

But you're missing a point, both ATi and nVidia are going to ship 512mb GDDR3 cards early next year.

I can't think of a game that will exist even in 2 years that will make a 512mb card do texture swapping off the ram.

and even in that situation, in 2 years we will probably have 10gBsec ram or something of that sort, so texture swapping will go unnoticed, imho

No, I do hear you *g*

It's logical that Game makers and developers avoid AGP Texturing, thus there technically should never be a real advantage of AGP 8x (= avoid at all cost, since it offers only 10% of the currently possible Onboard VRAM bandwidth).

It could be called a 'contingency' rather than a feature, when it actually comes into play.

And by the time we have a sustained 10GB/sec over RAM (in my estimate in about 5 years maybe, considering we're now at about ~3.5-4GB/sec with the fastest setups), we'll have Graphic Boards doing 20 times that bandwidth, resulting in the same situation again ;)

Anyway, fairly pointless discussion, since noone is really using 4x or 8xAGP except for those few % general acceleration (overhead) maybe, and that won't change.

I've found a Voodoo5 5500 PCI review which has a comparison between AGP/non-AGP in it.

http://www.firingsquad.com/hardware/v55500pci/default.asp

Seems that VDX is right, there is a 8-12% performance gain when using the agp version, for some reason.

Sergi