View Full Version : Not quite vintage--AMD Sempron vs. Socket 478 Pentium.

May 12th, 2013, 01:51 PM
Here's one that's been puzzling me. XP installed on two systems, same hard drive, etc.

The first is an ASUS A7N-266 Socket A motherboard. It has 1GB of PC2100 DDR installed and a Sempron 3000+ CPU installed.

The second is an IBM Netvista M 6792 Socket 478 1.8GHz Pentium 4 installed. It's populated with 512MB of PC133 SDRAM.

You'd expect that the Socket A box would be lots faster than the IBM, but it's not the case--the Netvista box is very noticeably faster.

Anyone have a clue as to why? I have to admit that I'm baffled. Maybe I'm just dense--were the Barton CPUs that much of an under-performer?

May 12th, 2013, 02:00 PM
The Sempron you have is 1.8Ghz, so it matches the P4. The Intel will also have more cache, as the Sempron is a budget CPU. So it's not toooo suprising - I think calling it the 3000+ might have been a bit optimistic.

Looking at old reviews, the 3000+ does seem to stomp on the Celeron, not sure about P4.

Also were they both fresh XP installs? Sometimes an old XP install can really bog down a machine.

May 12th, 2013, 02:07 PM
The 3000+ would be an Athlon XP with the Sempron badge (512K cache). The AMD CPU should blow the doors off of a 1.8Ghz P4, what video card are you using?

The FSB of the Sempron should be 333, PC2100 would be slowing it down a bit (don't think that motherboard supports anything above 266 anyway). What does the board say the CPU is when it posts, and do you have the latest BIOS installed?

May 12th, 2013, 02:11 PM
Sempron 3000+ has 128Kb cache, pretty sure the FSB is 200 but could be wrong.

Edit: internets confirmed this, so it must be true

Edit 2: a review versus an Intel Celeron D 2.66 http://www.hardwaresecrets.com/article/Sempron-3000+-and-Celeron-D-331-Review/404/2 - it does succesfully beat the Celeron on more than half of the tests. Something else I've found, is usually when you get a machine with a cheap AMD CPU, it also has a cheap motherboard, which could be a possible factor.

May 12th, 2013, 02:24 PM

He did say Barton core.

Celeron D would be later then Socket 478 correct( LGA 775)?

May 12th, 2013, 02:28 PM
I did a little digging. The IBM box stats are right, but I neglected to check inside the ASUS box before I posted. The memory is correct PC2100, but the CPU is wrong--Athlon XP 2000+, so FSB is 133MHz. CPU speed is 1.67 GHz. But that's not much slower than the Netvista setup and you'd think that DDR memory would give it a slight advantage of SDRAM.

Forget graphics--the lag in just launching a browser is very different between the two systems.

I was thinking about hanging on to this system because of legacy port support, including 2 floppies, but it sounds as if it would be better sent to the recyclers.

My wife likes the little Netvista box, so it might be worthwhile rehabilitating it with an upgraded mATX motherboard.

May 12th, 2013, 02:52 PM
The XP2000+ would be 266 memory bus (133 FSB). Could be a motherboard issue slowing it down (bad caps for example) or IBM just made a more stable board (if they made their own still at that point).

XP with 1GB should run faster then a system with 512MB even with the same CPU, are you sure the memory is correct on the AMD system?

Rick Ethridge
May 12th, 2013, 04:41 PM
My Barton 3000+ (2.11 GHz 512k cache) would run rings around a Pentium 1.8. I'm using it now and other than latency items it seems pretty spritely.

May 12th, 2013, 04:51 PM
The XP2000+ would be 266 memory bus (133 FSB). Could be a motherboard issue slowing it down (bad caps for example) or IBM just made a more stable board (if they made their own still at that point).

XP with 1GB should run faster then a system with 512MB even with the same CPU, are you sure the memory is correct on the AMD system?

That's my thought--but yeah, the BIOS and Control Panel->System both verify the configuration.

Would it be worth upgrading the AthlonXP+ to a Sempron 3300+? Or am I simply limited by the motherboard design?

You may wonder why I'm hanging on to these old boards....well, they don't take much space in storage, cost me nothing at this point, support floppy and IDE, COM etc. So I'm thinking it's probably worth hanging onto it.

May 12th, 2013, 05:04 PM
Athlon boards came in 266/333/400 FSB designs (and quite a few 400 FSB ones state that you can only use one PC3200 400 DIMM or you have to lower the memory speed for stability). The later 333/400 chips did have 512K cache making them pretty fast, but Athlon 64's blow them away. Very early XP boards were SDRAM based, or combo SDRAM/DDR and were limited to 266 FSB chips.

As far as spares go, I have a small mountain of Athlon XP boards mostly because I wanted faster 333/400 boards (they also have 8x AGP). They are cheap, but many have bad caps that cost a few dollars and some time to fix. They also tend to have non standard I/O shields that get annoying to source.

If it works I keep it, of it doesn't I fix it or toss it.

May 12th, 2013, 05:26 PM
Yeah, I've got an ASUS K8V that I keep around as a backup system. With a 3GHz Athlon 64, it's pretty spritely.

Update: Well, I had a careful look inside and where the manual says there are two jumpers to select the speed (BSEL0 and BSEL1), I have 4. The two additional are J3 and JEN with no references in the manual. Even stranger, the manual says that the fastest setting of the BSELx jumpers is 2-3. Silk-screened onto my motherboard is the legend that 1-2 is the fastest. If I add a jumper to JEN, I get a BIOS menu that allows me to pick the CPU multiplier from a list. I haven't yet figured out what J3 does. Weird, huh? The sticker on the board does identify it as an ASUS A7N-266-VM, so there's no mistake there.

An overclocker's delight, I guess, but you're still stuck with 33 MHz PCI.

June 7th, 2013, 09:50 PM
I thought I'd close this one out. I noticed on eBay that someone was selling a mobile Barton XP-M 2800+ for single-digit dollars, shipped. It was too tempting. I installed it in my system and was a bit taken aback to see that it was showing 800 MHz. After a bit of reading, I discovered that that was the standard boot-up speed of the mobile Bartons and PowerNow! would kick that up to the maximum--if your chipset had support for PowerNow!--and mine (NForce 2) didn't.


So back to the OC'ers forum and discovered that a simple pinmod to the motherboard would start the CPU up in its normal 16x multiplier. After a little soldering, I now have a system that runs at 2138MHz without overclocking. I haven't tried running it faster yet (I can change the FSB speed in the BIOS). The thing resides in an old Vectra VL desktop case and runs just fine off the original 120W PSU.

Yeah, I know it's silly, but this thing has real parallel and serial ports and supports 2 floppies, so why not?