The classic Pentium at 60MHz. This is the first Pentium-class CPU along with it's 66MHz counterpart.

Compared to a 486 the Pentium had several improvements including a superscalar architecture, 64-bit external databus and a faster Floating Point Unit (FPU). The superscalar architecture allows the Pentium to complete more than one instruction per clock cycle and the 64-bit databus allowed faster communication with the internal RAM. Due to the bigger bus SIMM's always have to be installed in pairs. One SIMM is 32-bit.

The FPU used pipelining (see this 486 that explains pipelining) to make it faster. The first Pentium CPU's (60~100MHz) had a problem in the FPU that resulted incorrect but predictable results. My Pentium 60 (as seen on the photo) also has the bug. The bug was detected in 1994 and eliminated in the end of 1994 meaning that only the oldest Pentium CPU's have the bug. Intel started a program to replace the bugged CPU's.

When running the Pentium 60 I noticed that both the chipset and the Pentium processor ran quite hot. The Pentium CPU needs 5V for operation which is a lot more compared to the newer Pentiums (P54; from 75MHz). Besides that everything ran normal. > Read more

"Pentium done right" in general sense. The core only needs 3,3V instead of 5V like the Pentium 60 or 66. Because of this, and the smaller production size, the heat output is a lot less. Also upgradeability is better as the socket 4 topped out at 66MHz (133MHz for expensive Overdrive chips) where normal socket 7 boards could go up to 133MHz for socket 5 systems.

Unfortunately the Pentium 75 only has a 50MHz front side bus which is a bit too narrow. It's faster brothers, at 90MHz and 100MHz, run noticeably faster because their FSB runs at 60MHz and 66MHz respectively. In the whole Pentium line-up it's clearly visible that 50MHz FSB parts fall behind 60MHz or faster FSB parts. It's no wonder that if you run a Pentium 150 at 3x50MHz FSB it will not be faster than a Pentium 133 (2x66MHz FSB) in overall performance. Try Doom for example; it will run with about 72FPS which is slower than the Pentium 120! Luckily the Pentium 150 uses a 60MHz bus . > Read more

44 weeks older and uses a gold heatspreader for better heat distribution. Besides that it's not much different compared to the newer/regular Pentium 75. > Read more

Same as the Pentium 75 but then a tad faster due to higher core clock frequency and front side bus. Especially the front side bus has a great impact on this CPU. It clearly jumps ahead on the 75. > Read more

As with the Pentium 75's: the 90MHz model was also available with both integrated heatspreader as full ceramic packaging. The older CPU's have a gold colored heatspreader whereas the newer ones are fully ceramic. > Read more

In March 1994 this CPU was launched along with the 90MHz model. The 100MHz part was top of the line and ran far ahead on every other x86 CPU. It's a tad faster than the 90MHz because both core and bus frequency are higher. It took Intel exactly one year to release the Pentium 120MHz and two years (March 1996) for AMD to get it's AMD K5 ready. > Read more

Same as this Pentium 100 except for the production date, sSpec number and core stepping. This one is older (17th week of 1995) and has core stepping C2. > Read more

Dozens of Pentium CPU's exist and this is just one of them. I have more Pentiums running at 100MHz but they are all a tad different because the sSpec number differs. > Read more

I don't see these Pentiums much . Normally they don't have a boxed heatsink and the ones that come by with boxed heatsink often have a silver like top. This one has blue letters indicating it's an Intel Pentium. > Read more

Successor of the Pentium 100 that was on the market for a year before the Pentium 120 came. Despite it's slower bus it's quite a bit faster than the Pentium 100. A 60MHz FSB seems to fit the Pentium CPU quite well at these low (90MHz, 120MHz) clock frequencies. At higher clock frequencies (150MHz) the 60MHz is getting a bit narrow for applications that need a fast graphics card like games. > Read more

Same as this Pentium 120 but then with different sSpec number. > Read more

The Pentium 133 is the slowest Pentium that uses the P54CS-core. The P54CS is the successor of the P54CQS and is used in 133, 150, 166 and 200MHz (without MMX) models. > Read more

Same as this Pentium 133 except for the production date and the iComp index etched into the processor. This processor, which is about half a year newer then the other one, has the iComp2 index. iComp stands for Intel Comparative Microprocessor Performance. The first iComp was used on the 486SX25 and as processors got newer and faster there was the need for a new version of iComp, called iComp 2.0. This can be found on Pentium 120 or higher. > Read more

The Pentium 150 wasn't sold much because it had a slower FSB compared to the Pentium 133 and thus was less efficient and most people went for a Pentium 166 instead if they wanted performance. See the benchmarks that show the performance of the Pentium 150. Especially games (MDK, Doom and Quake) run quite poor on this CPU. Office-like applications don't need a fast bus or fast access to a graphics card so for those applications this CPU runs just fine.

Basically the Pentium 150 is just like the Pentium 133 but then with a different FSB / multiplier configuration. > Read more

For about 6 months this was the fastest CPU around. After that the 200MHz Pentium made it's debut and took the lead. At the time the Pentium 166 became affordable Cyrix and AMD had their 166MHz parts available. In general they were as good as the Pentium for business/office applications. In case you needed FPU performance (floating point, like CAD/CAM or games) the Pentium was your choice. > Read more

First of all: this CPU is fake!

Some people take lower-end CPU's, modify (overclock) them to look like a faster model and sell them. This practice has been around for years and has been done quite recently as well. You can find fake 386 and 486 as well which often have something taped over that says it's a faster model. For example a 50MHz CPU is sold as 66MHz.

These gold CPU's are a bit different, though. They didn't modify the (ceramic) CPU but took a mobile CPU and build a gold (but actually good looking) cover around it. Everything is made very well and the CPU works well, too.

Modern examples of fake CPU's are the AMD Athlon XP. These CPU's don't have a CPU string so the name of the CPU (which you see in Windows or CPU-z) is generated by the BIOS. If you take a 2500+, tape over the OPN code so it will show 3200+, then people will configure it as a 3200+ (which has a faster FSB but the same multuplier) and the BIOS will show AMD Athlon XP 3200+. There you go: you made more than a 100$ profit.

How to recognize these fake CPU's? In this case it's pretty obvious because of the gold packaging. Sometimes it's difficult but look carefully. Often the font is a bit different or the position of the words doesn't match. Also check the OPN or sSpec code. Take a look at the SL25J sSpec code on this CPU which is from a Pentium 120! In some cases the production date doesn't appear to be valid; fakers seem to generate a random number but when you're into these number you can read the production date. Some CPU's are made after week 52/53 from a particular year which is not possible.

If you ever find one of these CPU's and want to open it (like I did) be careful! You can pop open the top with a screwdriver but be careful when cleaning the 'die' (core; the chip in the middle). It has very tiny connections/lines and if you move them they can break or short as soon as you power up the CPU. > Read more

The top-of-the-line Pentium processor. The only Pentiums that are faster are the Pentium MMX but they are not similar to the first kind of Pentium. I've never seen a Pentium 200MHz system running in real life as they were quite expensive back in the days this thing was new. By the time 166MHz and 200MHz parts became feasible to buy the Pentium MMX was widely available.

Because the Pentium MMX uses a lower voltages some older motherboards can not run the MMX processor. You have to use a classic Pentium instead and if you're looking to boost your system to the fastest Pentium the 166MHz and especially 200MHz are the way to go .

Also note that the Pentium 200 uses the new PPGA (Plastic Pin Grid Array) instead of CPGA which is made of ceramic. Most Pentium MMX CPU's use PPGA as well but there are some ceramic versions as well. > Read more