# The Socket 754 Mac



## devguy (Jun 16, 2010)

So, here's an interesting project I've been working on for a while.  I know this is supposed to more of a log than a show off, but it is still a WIP.  I hope you all enjoy these as much as I do.  My goal was to make the most primitive AMD-powered MacOS X computer.  I chose Socket 754 as they were the first to introduce SSE2 to the AMD processors.  I've never owned a chip on this socket before, as I jumped directly from Socket A onto Socket 939, so this was a fun experience.  However, what I found interesting is that the exact processor revision I chose for my socket 939 machine (the 90nm Venice) actually was released for the socket 754!  Thus, that became the centerpiece for my new machine as SSE3 support (available on the Venice core) is much preferred over only having SSE2.

As the PC I built was slightly under-powered when compared with say a modern Intel Mac, I had every intention of picking the right parts for overclocking.  As I mentioned, I never used socket 754 before, and so I asked the opinions of others, all of which told me legendary tales of the DFI Lanparty UT.  I really wanted one of those, but they are extremely hard to get ahold of (as if nice socket 754 motherboards weren't already hard enough to find).  So instead, I found someone selling an Athlon 64 NewCastle + Gigabyte K8NS-Pro board for $30 which appeared to be a good option.  Unfortunately, after all my parts arrived I could not get the board to post with the CPU (fans wouldn't even spin up).  I tested all the equipment separately, but all to no avail.  Even after several emails, the bloody bastard never got back to me, so I'm out the dough.  :shadedshu  Finally, I bought an ASUS K8N board off eBay.

Reading about overclocking the Clawhammer and NewCastle cores, I was very happy to end up with a Venice!  I originally put the 2800+ Clawhammer in my K8N to update the BIOS for Venice support, and was surprised to see the Clawhammer at about 44C at idle in the BIOS.  Geez!  My Venice sits around 36C idle in the BIOS, which is much better!

As far as actually overclocking the Venice, it is interesting.  In order to get things prepared, I installed Windows XP x64 as my testing OS (Vista/7 has no real driver support for the nForce 3 - Thanks nVidia!).  This is the exact OS I used back when I had my socket 939 Venice in an old TForce939-6100 (I hope that brings back some nice memories to some of you).  With that 939 Venice, no matter what I did, once I tried to get past 2.4Ghz, I always got errors no matter how much voltage was thrown at the chip (temps were always fine under a Zalman 8700CNPS).  Interestingly, this socket 754 Venice had the EXACT same limitation!  No matter what I do, I cannot get it to prime for more than 5 minutes any higher than 2.4Ghz (although it is perfectly 3D stable at 2.5Ghz).  Looking around on websites, 2.7Ghz was usually expected from the Venice, with 2.8Ghz usually attainable.  2 Venice chips that have the same issue!  What is the deal?

Well, as it turns out all the reviews at the time of the Venice are run on XP x86.  I was using XP x64 both then and now.  I had no idea how much impact the AMD64 ISA impacted stability (especially on the old Venice).  So, any of you trying to overclock processors (particularly these older-gen AMD64 chips) on a 64bit OS and aren't getting as high as everyone else, check if they are using a 32bit OS.  There's a reason why all world record CPU benchmarks are done on a 32bit OS.  In the end, since Leopard 10.5.8 is a 32bit OS, I ended up at a stable 2.5Ghz with 1.5V.  On my K8N board, the next VCORE value the board would produce was 1.65V, which is too much IMHO for a 90nm Venice for 24/7.

The video card was also something I wanted to overclock.  Having an HD series video card isn't as important in the Mac world as in the Windows/Linux world, but I still found it desirable.  As I already had experience with a Radeon 2400pro AGP being slow as molasses, I decided to move up a notch to the 2600Pro AGP.  Unfortunately, the card is crippled majorly by DDR2 RAM onboard rather than gDDR3 (or even gDDR4 on some high end 2600xt boards).  Oddly though, this board had a PCIe power connector (yes, for an AGP card ), so I wondered about its overclocking potential.  Well, it certainly was decent, as I ended with clocks near the 2600xt boards that have DDR2 RAM.  Not bad!  And since there is no easy ATI overclocker in OS X, I flashed those values to the video cards BIOS.  As a note, to all those trying to flash the BIOS of an ATI AGP card from the X800 onwards, do not flash the Ritera bridge chip (I didn't either, but it is an easy mistake to make) when using ATIFLASH.

For mods, I did some decent cable management (not easy with a non-modular PSU!).  Also, as nice as the case is, for some reason, it has no hole at the top (above the motherboard) for an EPS12V cable to come through.  Thus, rather than letting it go up the front of the motherboard, I drilled a hole in the case to allow that (I suppose some people might try to stick it through the CPU backplate hole, but there might not be enough room).  Finally, I purchased a Zalman NB-47J northbridge heatsink for the Gigabyte board, but since that board did not work out, I didn't want to waste it.  However, on the ASUS board, the AGP card would be blocked by such a tall heatsink.  So, I bended the fins downward to fit the AGP card in!

Enough chatter, here's the specs and some pictures!











Specs:
CPU: AMD Athlon 64 3000+ @ 2.5Ghz (1.5V)
Memory: 2x1GB Crucial Value RAM PC3200 @ DDR454-3-3-3-8-2T (hand selected Micron 5B-F sticks!)
Video Card: Visiontek Radeon HD 2600 Pro AGP 512mb DDR2 @ 769/525 (from 600/400)
Motherboard: ASUS K8N socket 754 motherboard (nForce3 250gb)
Case: NZXT M59
PSU: Corsair 400W (non-modular cause it was cheap )
HDD: Maxtor 100GB ATA/133
DVD-ROM: Samsung 616E ATAPI
Audio: Sound Blaster Live 5.1
Cooling: Zalman CNPS9700LED, Zalman NB-47J


As for the Leopard part of this discussion:  Originally, I wanted Snow Leopard 10.6.3, and after quite a battle to get it running on this machine, I finally gave up when I found out I wouldn't be able to get 3D hardware acceleration with the 2600 Pro.  Also, Snow Leopard isn't a really good option for AMD machines right now, as there is no on the fly patcher for executables to make them AMD friendly.  Thus, too much crap to deal with, and I decided to stick with 10.5.8 (which I recently got acquainted with as I have it running on my main machine from within VirtualBox x64).

With this board, I was essentially forced to use the PATA bus, as the SATA bus doesn't have AHCI support (necessary to not get a kernel panic with SATA drives).  Also, I couldn't use the Vanilla kernel because it is an AMD machine, so I went with a Voodoo derivative kernel.  After getting video/audio drivers installed (I used the KX project sound drivers), I had a very useable machine with Quartz Extreme support!

As far as performance goes, it is very weird, and any AMD OSX86 experts, I'd like some help here.  The machine plays back 720p without any problem using VLC, but with 1080p video, it plays near smooth, but with a slightly noticeable lack of smoothness (really hard to explain, but it isn't butter smooth like in Windows).  What is weird though, is that even at 1080p, the CPU usage is only around 75%.  

Then, there's games.  Naturally, the first game I tried was Halo.  Performance is very odd, and doesn't seem to change much between 800x600 and 1920x1080p.  Does this imply a CPU bottleneck?  I would think that an Athlon 64 and 2600pro would handle Halo 1 fine at 1080p if most people could play Halo Mac smoothly with a G4 and 9800pro!  Also, I tried installing Steam, and then Half-Life2.  Every-time I start HL2, it always hangs right when the main menu should display.  This also happens with Episode 1.  Any ideas?  Finally, Wolfenstein: ET hangs on the opening video.  Any ideas would be nice!


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## Melvis (Jun 16, 2010)

Interesting read  

Nice Skt 754 rig you have there 

I did the same thing jumped from Skt A to 939 then to AM3 lol


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## TechPowerDown (Jun 25, 2010)

Looks Good. Went From P3 To Skt A Then AM2, Then AM3, Good Decision.


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## m1dg3t (Jun 25, 2010)

Nice "classic" build  

1 Suggestion: Move the audio card down a slot or 2 so the GFX can breathe a lil' better


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