Shuttle HOT-661V Apollo Pro Plus Slot-1

While there are jumpers onboard, the 661V can be used as a jumperless boards in most situations. When the clock multiplier jumper block is set to BIOS Setup, as is the default setting, the FSB and clock multipliers can be selected directly in BIOS. Note, however, that the 661V does by default detect the state of B21, meaning that speeds of 100MHz and up are only available to processors intended for 100MHz operation. A quick look through the manual reveals that there is a jumper in between the DIMM slots and the Slot-1 connector that essentially controls the state of B21. By opening up this jumper, a 66MHz CPU looks to the motherboard like it was intended for 100MHz operation and, thus, allowing you to select any FSB speed for those overclockers out there. It is also possible to configure the CPU settings manually via jumpers on the board. If a clock multiplier is selected, the board automatically becomes a fully jumpered board.

A plethora of FSB speeds are available in the BIOS. in addition to the officially supported 66 and 100MHz settings - 103/105/110/112/115/120/124/133. For those of you with 66MHz CPU's, FSB speeds of 75 and 83 are also available for overclocking. Unlike some other motherboards available these days, the PCI bus is always derived from the FSB clock by a 1/3 multiplier so that at 120/124/133MHz the PCI bus is running way out of spec at 40/41/44MHz respectively. If you plan to use one of these speeds, make sure your peripherals can handle it. A few other motherboards have a 1/4 multiplier to produce a 33MHz PCI speed with a 133MHz FSB setting to keep everything within spec. All those bus speeds should allow for lots of overclocking madness - much more than most other motherboards. For example, if you cannot quite reach 124MHz because of your CPU, SDRAM, or peripherals, you no longer have to step all the way back down to 112MHz thanks to those in between settings of 115 and 120MHz.

Oddly enough, the installation guide claims support for 112/133/140/150MHz FSB, but not the other settings above 100MHz that were in the BIOS. The 140 and 150MHz settings are not found in the BIOS., but would not POST either, making them essentially useless. This could be due to the incredibly out of spec PCI or AGP buses (both PCI and AGP video cards were tried) or memory that could not handle the high speeds. Of course, it is also possible that the motherboard simply cannot handle such high speeds. Regardless, the 140/150 settings were unusable for AnandTech.

The virtually standard Award 4.51PG BIOS. is featured on the 661V with a few extra settings for the Apollo Pro Plus chipset. The FSB settings are found under "Chipset Features Setup." Settings for enabling AGP 2x and configuring the AGP aperture size are available there as well. Interestingly, there are actually settings for configuring the SDRAM timing - something that is almost always automatically done these days via the SDRAM SPD. Options for SDRAM timing include normal, turbo, 8ns, and 10ns. A separate option toggles one of the Apollo Pro Plus's most unique features - the ability to run your SDRAM at the FSB speed or the AGP speed. With this option, one can use their old PC66 SDRAM in conjunction with 100MHz bus speeds - perfect for all you upgraders out there. This setting can even help out when trying to use some of the higher bus speeds if your SDRAM just can't quite make it. It would have been extremely useful in getting 140/150MHz FSB to be stable, but those settings did not work at all.

The standard Shuttle bundle is included and features their Installation Guide, a universal CPU retention mechanism that works with both Pentium II and Celeron CPU's, and finally the Spacewalker Supplementary CD-ROM that also includes an online version of the full 661V manual.

Power management consists of pretty much the standard stuff these days. A wake on-LAN header is available to allow the system to resume on network activity and the BIOS. can be set to turn on the system at a specific time. The CPU fan can be shut off when the system suspends to quiet things down a bit. ACPI support is built into the BIOS. for added power management under an ACPI compliant OS like Windows 98.