Modding ancient AGP slots is still oddly popular in 2024 to add modern GPUs and boost networking — two adaptors enable GTX 960

Shot from RECNAS' AGP to PCI networking mod.
Shot from RECNAS' AGP to PCI networking mod. (Image credit: RECNAS on YouTube)

Strangely enough, the past few months of 2024 have seen prominent discussions of a few modern-day AGP (Accelerated Graphics Port) mods — the first is a mod of questionable practicality to get a GTX 960 working on an AGP board, which took considerable gymnastics. The second involves repurposing an AGP port on a Super Socket 7 motherboard for faster, more modern networking speeds.

Tercio_miranda recently posted a mod from a retro PC gaming community on Facebook. The process (pictured below) involved using both an AGP-to-PCI and a PCI-to-PCIe adapter to install a GTX 960 onto an ancient motherboard. 

The AGP interface is newer and, thus, likely faster than the PCI interface on the motherboard, so using the first adapter is highly questionable; however, the user probably didn't have a PCI to PCIe adaptor handy. The GPU is ultimately listed in an included AIDA64 screenshot, showing that it is functional. The user didn't share performance benchmarks, but this setup may be enough for Crysis.

Photograph of the AGP-to-PCI mod attached to the PCI-to-PCIe mod needed to install a GTX 960 in an old Athlon XP 2400+ PC.

Photograph of the AGP-to-PCI mod attached to the PCI-to-PCIe mod needed to install a GTX 960 in an old Athlon XP 2400+ PC. (Image credit: Christian Rudewig on FB (via @tercio_miranda on Twitter))

For instance, back in August of 2009, Don Woligroski, writing for Tom's Hardware, used an OC'd CPU and a powerful native AGP card to get Crysis running at 65 FPS on Low Physics on an AGP board originally released in November 2005. PCIe debuted in 2003, so this was well after many faster boards with newer standards were already on the market. This means that, yes, AGP could run Crysis while it was still common, and it remained one of the most demanding games on PC for several years after its 2007 release.

People still test games with it these days, though Crysis: Remastered and its ray tracing are definitely the more intensive choice for modern, non-AGP graphics cards.

YouTuber RECNAS also has a minute-long YouTube video that highlights his Super Socket 7 motherboard and, subsequently, an AGP-to-PCI networking adapter. Since RECNAS wanted to repurpose this roughly late 90s-era Super Socket 7 motherboard as a NAS, he didn't want to be relegated to the slower, shared PCI bandwidth on the board.

This means that if he could get the NAS running through the fastest available port on the board, AGP, he could achieve the speed he's looking for. We've embedded the original video of him achieving this below.

After testing with the AGP-to-PCI adapter, he's achieved just over 200 MB/s throughput on his Super Socket 7 Board. The exact reading averages 198 Mebibytes per second, which converts to roughly 207 MB/s. This is compared to the reported shared PCI bandwidth of 133 MB/s, or more realistically, 92 MB/s, according to RECNAS.

Now, the maximum rate of the original AGP port is 533 MB/s, and AGP 3.5 eventually phased out at 2133 MB/s— but as the name implies, these ports were targeted at graphics expansions, not storage. The later stage of AGP graphics support could get pretty interesting, though, especially if you were willing to overclock your AGP-supported motherboard.

As you can see, the modding community is still hard at work wringing more functionality out of old gear, either for entertainment or out of necessity. 

  • ezst036
    Going through some serious stress and thought just to stick to Windows XP.
    Reply
  • bit_user
    Not sure if "popular" is a word I'd use, but it's definitely a thing.

    Just wanted to point out that AGP and PCI are closely related, making the adapter probably somewhat straight-forward to implement. Also, if the AGP -> PCI adapter ran a 66 MHz (the native speed of AGP 1.0), that would still give you a 2x boost over legacy PCI, which typically ran at just 33 MHz.
    Reply
  • Alvar "Miles" Udell
    Don't remind me of AGP, had to replace a X1950Pro AGP a few months after I bought it with an X1950GT PCIe because of a motherboard change way back in 2007.
    Reply
  • bit_user
    Alvar Miles Udell said:
    Don't remind me of AGP, had to replace a X1950Pro AGP a few months after I bought it with an X1950GT PCIe because of a motherboard change way back in 2007.
    When I bought my Pentium 4, I had the choice of going with AGP + DDR or PCIe + DDR2. Initially, DDR2 had higher latency and with PCIe being such a new standard, I opted for tried-and-true AGP and regular DDR.

    I didn't really regret that decision until about my second GPU upgrade for that machine. I got stuck with a HD 4650, probably using regular DDR3 (not GDDR3), because it was basically the fastest modern thing still available for AGP.
    Reply
  • Alvar "Miles" Udell
    bit_user said:
    When I bought my Pentium 4, I had the choice of going with AGP + DDR or PCIe + DDR2. Initially, DDR2 had higher latency and with PCIe being such a new standard, I opted for tried-and-true AGP and regular DDR.

    I didn't really regret that decision until about my second GPU upgrade for that machine. I got stuck with a HD 4650, probably using regular DDR3 (not GDDR3), because it was basically the fastest modern thing still available for AGP.

    It didn't help that it took a while before GPUs started really exceeding AGP bandwidth, so many people (like me) didn't see the need to go PCIe at first. Thankfully an X1950GT was only $140 so it wasn't AS bad as it could have been...
    Reply
  • Vanderlindemedia
    To be fair, when that switch came from AGP to PCI-E there was zero difference in speeds for the cards back at the time. The reason why was the industrialisation in both enterprise and consumer market knowing how many different standards there where at that time.

    AGP is afteral a direct link to the CPU instead of over the chipset or through other PCI devices. You can run a soundcard on it if you have the proper tools and drivers for it. OC'ing both PCI-E bus or AGP bus was "fun" - reward was there in actual percentages.

    I remember running a card over 119Mhz PCI-E - increasing the whole speed of the bus was simply how faster bits would go from one to another point.
    Reply
  • bit_user
    Vanderlindemedia said:
    AGP is afteral a direct link to the CPU instead of over the chipset or through other PCI devices.
    Not exactly. AGP did go through the chipset, but you're right that it didn't share the link with any other devices.

    Vanderlindemedia said:
    OC'ing both PCI-E bus or AGP bus ...
    PCI was the last true bus, in PCs. PCIe is not a bus - it is a packet-switched network.

    That said, I think AGP was technically a bus, even though it was implemented as a point-to-point link.
    Reply
  • Vanderlindemedia
    Oh, your right:

    The primary advantage of AGP is that it doesn't share the PCI bus, providing a dedicated, point-to-point pathway between the expansion slot(s) and the motherboard chipset. The direct connection also allows higher clock speeds.

    But it's still a link offering more bandwidth. You can place anything in between that can translate AGP signals into PCI-E signals and virtually attach anything you want.
    Reply
  • Alvar "Miles" Udell
    Vanderlindemedia said:
    Oh, your right:



    But it's still a link offering more bandwidth. You can place anything in between that can translate AGP signals into PCI-E signals and virtually attach anything you want.

    That's what several board partners did during that time, used a Rialto PCIe-AGP bridge

    https://www.theregister.com/2004/10/06/ati_rialto/
    Reply
  • stonecarver
    Darn you Tom's putting this article up is like waving hardware crack. :rofl:

    Thank god I only have two AGP boards left and filled with a card. But it's nice to see yet again where everyone says you can't, here it's been done.
    Reply